Abstract

Most pollsters base their election projections off questions of voter intentions, which ask “If the election were held today, who would you vote for?” By contrast, we probe the value of questions probing voters’ expectations, which typically ask: “Regardless of who you plan to vote for, who do you think will win the upcoming election?” We demonstrate that polls of voter expectations consistently yield more accurate forecasts than polls of voter intentions. A small-scale structural model reveals that this is because we are polling from a broader information set, and voters respond as if they had polled twenty of their friends. This model also provides a rational interpretation for why respondents’ forecasts are correlated with their expectations. We also show that we can use expectations polls to extract accurate election forecasts even from extremely skewed samples.

I. Introduction

Since the advent of scientific polling in the 1930s, political pollsters have asked people whom they intend to vote for; occasionally, they have also asked who they think will win. Our task in this paper is long overdue: we ask which of these questions yields more accurate forecasts. That is, we evaluate the predictive power of the questions probing voters’ intentions with questions probing their expectations. Judging by the attention paid by pollsters, the press, and campaigns, the conventional wisdom appears to be that polls of voters’ intentions are more accurate than polls of their expectations.

Yet there are good reasons to believe that asking about expectations yields more greater insight. Survey respondents may possess much more information about the upcoming political race than that probed by the voting intention question. At a minimum, they know their own current voting intention, so the information set feeding into their expectations will be at least as rich as that captured by the voting intention question. Beyond this, they may also have information about the current voting intentions—both the preferred candidate and probability of voting—of their friends and family. So too, they have some sense of the likelihood that today’s expressed intention will be changed before it ultimately becomes an election-day vote. Our research is motivated by idea that the richer information embedded in these expectations data may yield more accurate forecasts.

We find robust evidence that polls probing voters’ expectations yield more accurate predictions of election outcomes than the usual questions asking about who they intend to vote for. By comparing the performance of these two questions only when they are asked of the exact same people in exactly the same survey, we effectively difference out the influence of all other factors. Our primary dataset consists of all the state-level electoral presidential college races from 1952 to 2008, where both the intention and expectation question are asked. In the 77 cases in which the intention and expectation question predict different candidates, the expectation question picks the winner 60 times, while the intention question only picked the winner 17 times. That is, 78% of the time that these two approaches disagree, the expectation data was correct. We can also assess the relative accuracy of the two methods by assessing the extent to which each can be informative in forecasting the final vote share; we find that relying on voters’ expectations rather than their intentions yield substantial and statistically significant increases in forecasting accuracy. An optimally-weighted average puts over 90% weight on the expectations-based forecasts. Once one knows the results of a poll of voters expectations, there is very little additional information left in the usual polls of voting intentions. Our findings remain robust to correcting for an array of known biases in voter intentions data.

The better performance of forecasts based on asking voters about their expectations rather than their intentions, varies somewhat, depending on the specific context. The expectations question performs particularly well when: voters are embedded in heterogeneous (and thus, informative) social networks; when they don’t rely too much on common information; when small samples are involved (when the extra information elicited by asking about intentions counters the large sampling error in polls of intentions); and at a point in the electoral cycle when voters are sufficiently engaged as to know what their friends and family are thinking.

Our findings also speak to several existing strands of research within election forecasting. A literature has emerged documenting that prediction markets tend to yield more accurate forecasts than polls (Wolfers and Zitzewitz, 2004; Berg, Nelson and Rietz, 2008). More recently, Rothschild (2009) has updated these findings in light of the 2008 Presidential and Senate races, showing that forecasts based on prediction markets yielded systematically more accurate forecasts of the likelihood of Obama winning each state than did the forecasts based on aggregated intention polls compiled by Nate Silver for the website FiveThirtyEight.com. One hypothesis for this superior performance is that because prediction markets ask traders to bet on outcomes, they effectively ask a different question, eliciting the expectations rather than intentions of participants. If correct, this suggests that much of the accuracy of prediction markets could be obtained simply by polling voters on their expectations, rather than intentions.

These results also speak to the possibility of producing useful forecasts from non-representative samples (Robinson, 1937), an issue of renewed significance in the era of expensive-to-reach cellphones and cheap online survey panels. Surveys of voting intentions depend critically on being able to poll representative cross-sections of the electorate. By contrast, we find that surveys of voter expectations can still be quite accurate, even when drawn from non-representative samples. The logic of this claim comes from the difference between asking about expectations, which may not systematically differ across demographic groups, and asking about intentions, which clearly do. Again, the connection to prediction markets is useful, as Berg and Rietz (2006) show that prediction markets have yielded accurate forecasts, despite drawing from an unrepresentative pool of overwhelmingly white, male, highly educated, high income, self-selected traders.

While questions probing voters’ expectations have been virtually ignored by political forecasters, they have received some interest from psychologists. In particular, Granberg and Brent (1983) document wishful thinking, in which people’s expectation about the likely outcome is positively correlated with what they want to happen. Thus, people who intend to vote Republican are also more likely to predict a Republican victory. This same correlation is also consistent with voters preferring the candidate they think will win, as in bandwagon effects, or gaining utility from being optimistic. We re-interpret this correlation through a rational lens, in which the respondents know their own voting intention with certainty and have knowledge about the voting intentions of their friends and family.

Our alternative approach to political forecasting also provides a new narrative of the ebb and flow of campaigns, which should inform ongoing political science research about which events really matter. For instance, through the 2004 campaign, polls of voter intentions suggested a volatile electorate as George W. Bush and John Kerry swapped the lead several times. By contrast, polls of voters’ expectations consistently showed the Bush was expected to win re-election. Likewise in 2008, despite volatility in the polls of voters’ intentions, Obama was expected to win in all of the last 17 expectations polls taken over the final months of the campaign. And in the 2012 Republican primary, polls of voters intentions at different points showed Mitt Romney trailing Donald Trump, then Rick Perry, then Herman Cain, then Newt Gingrich and then Rick Santorum, while polls of expectations showed him consistently as the likely winner.

We believe that our findings provide tantalizing hints that similar methods could be useful in other forecasting domains. Market researchers ask variants of the voter intention question in an array of contexts, asking questions that elicit your preference for one product, over another. Likewise, indices of consumer confidence are partly based on the stated purchasing intentions of consumers, rather than their expectations about the purchase conditions for their community. The same insight that motivated our study—that people also have information on the plans of others—is also likely relevant in these other contexts. Thus, it seems plausible that survey research in many other domains may also benefit from paying greater attention to people’s expectations than to their intentions.

The rest of this paper proceeds as follows, In Section II, we describe our first cut of the data, illustrating the relative success of the two approaches to predicting the winner of elections. In Sections III and IV, we focus on evaluating their respective forecasts of the two-party vote share. Initially, in Section III we provide what we call naïve forecasts, which follow current practice by major pollsters; in Section IV we product statistically efficient forecasts, taking account of the insights of sophisticated modern political scientists. Section V provides out-of-sample forecasts based on the 2008 election. Section VI extends the assessment to a secondary data source which required substantial archival research to compile. In Section VII, we provide a small structural model which helps explain the higher degree of accuracy obtained from surveys of voter expectations. Section VIII characterizes the type of information that is reflected in voters’ expectation, arguing that it is largely idiosyncratic, rather than the sort of common information that might come from the mass media. Section IX assesses why it is that people’s expectations are correlated with their intentions. Section VI uses this model to show how we can obtain surprisingly accurate expectation-based forecasts with non-representative samples. We then conclude. To be clear about the structure of the argument: In the first part of the paper (through section IV) we simply present two alternative forecasting technologies and evaluate them, showing that expectations-based forecasts outperform those based on traditional intentions-based polls. We present these data without taking a strong position on why. But then in later sections we turn to trying to assess what explains this better performance. Because this assessment is model-based, our explanations are necessarily based on auxiliary assumptions (which we spell out).

Right now, we begin with our simplest and most transparent comparison of the forecasting ability of our two competing approaches.

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• Forecasting Elections: Voter Intentions versus Expectations

Editor's Note: A new academic study by David Rothschild and Justin Wolfers concludes that poll questions about expectations—which ask people whom they think will win—have historically been better guides to the outcome of presidential elections than traditional questions about people’s preferences. David Leonhardt of The New York Times conducted an interview with Wolfers by e-mail, focusing on the implications of the study for current presidential polls.

David Leonhardt:In the article, I discussed only briefly the expectations polls about the 2012 race, and some of the Twitter feedback was eager for more. By my count, there have been five recent major polls asking people whom they expect to win — by ABC/Washington Post, Gallup, Politico/George Washington University, New York Times/CBS News, and the University of Connecticut. There is also sixth from Rand asking people the percentage chances they place on each candidate winning. How consistent are the polls?

Justin Wolfers: There’s a striking consistency in how people are responding to these polls. The most recent data are from the Gallup poll conducted Oct. 27-28, and they found 54 percent of adults expect Obama to win, versus 34 percent for Romney. Around the same time (Oct. 25-28), there was a comparable New York Times/CBS poll in which 51 percent of likely voters expect Obama to win, versus 34 percent for Romney.

But these results aren’t just stable across pollsters, they’ve also been quite stable over the past few weeks, even as the race appeared to tighten for a while. Politico and George Washington University ran a poll of likely voters on Oct. 22-25, finding 54 percent expect Obama to win, versus 36 percent for Romney. The University of Connecticut/Hartford Courant poll of likely voters got a somewhat higher share not venturing an answer, with 47 percent expecting Obama to win versus 33 percent for Romney. Finally, the ABC/Washington Post poll of registered voters run Oct. 10-13 found 56 percent expect Obama to win, compared to 35 percent for Romney.

I’m rather surprised by the similarities here – across time, across pollsters, across how they word the question, and across different survey populations (likely voters, registered voters, or adults) – but I suspect that is part of the nature of the question. You just don’t see the noise here that you see in the barrage of polls of voter intentions, which are extremely sensitive to all of these factors.

I always throw out the folks who don’t have an opinion, and count the proportions as a share of only those who have an opinion. By this measure, the proportion who expect Obama to win is: 61 percent (Gallup), 60 percent (The New York Times), 60 percent (Politico), 59 percent (Hartford Courant), 62 percent (ABC). The corresponding proportions who expect Romney to win are: 39 percent, 40 percent, 40 percent, 41 percent and 38 percent. Taking an average across all these polls: 60.3 percent expect Obama to win. Or if you prefer that I focus only on the freshest two polls, 60.7 percent expect him to win.

DL: The results do seem have tightened somewhat since the first debate, which Romney was widely seen to have won, right? Do the patterns — or lack of patterns — in the numbers help solve the issue of what most people are thinking of when they answer the expectation question: Private information (their friends’ voting plans, yard signs in their neighborhood, etc.) or public information (media coverage, speeches, etc.)?

JW: The results of the polls of voter intentions seem to have tightened a bit since the first debate. There’s an interesting school of thought in political science that basically says: voters are pretty predictable. But they don’t think too hard about how they’re going to vote until right before the election. So what happens is that public opinion through time just converges to where it “should” be. And viewed through this lens, the first debate was just an opportunity for people who really should always have been in Romney’s camp to figure out that they’re in Romney’s camp.

So why did the expectations polls move less sharply than intentions polls? One possibility is that your expectations are explicitly forward-looking, and perhaps people saw the race tightening as they saw that some of the support for Obama was a bit soft. Let me put this another way: There are two problems with how we usually ask folks how they plan to vote. First, the question captures the state of public opinion today, while the expectations question effectively asks you where you think public opinion is going. And second, polls typically demand a yes or no answer, when the reality may be that we know that our support is pretty weak, and it may change, or we aren’t even sure whether we’ll turn up to the polls. The virtue of asking about expectations is that you can think about each of your friends, and think not just about who they’re supporting today, but also whether they may change their minds in the future.

I worry that it sounds a bit like I haven’t answered your question, but that’s because I don’t have a super-sharp answer. If I had to summarize, it would be: expectations questions allow you to think about how the dynamics of the race may change, and so they are less sensitive to that change when it happens.

DL: Based on your research and the current polls, what does the expectations question suggest is the most likely outcome on Tuesday?

JW: If a majority expects Obama to win, then right there, it says that I’m forecasting an Obama victory.

But by how much? Here’s where it gets tricky. The fact that 60 percent of people think that Obama is going to win doesn’t mean that he’s going to win 60 percent of the votes. And it doesn’t mean that he’s a 60 percent chance to win. Rather, it simply says that given the information they have, 60 percent of people believe that Obama is going to win. Can we use this to say anything about his likely winning margin?

Yes. I’ll spare you the details of the calculation, but it says that if 60.3 percent of people expect Obama to beat Romney, then we can forecast that he’ll win about 52.5 percent of the two-party vote. That would be a solid win, though not as impressive as his seven-point win in 2008.

The proportion who expect Obama to win right now looks awfully similar to the proportion who expected George W. Bush to win in a Gallup Poll at a similar point in 2004. Ultimately Bush won 51.2 percent of the two-party vote.

Right now, Nate Silver is predicting that Obama will win 50.5 percent of the popular vote, and Romney 48.6 percent. As a share of the two-party vote, this says he’s forecasting Obama to win 51 percent of the vote. Now Silver’s approach aggregates responses from hundreds of thousands of survey respondents, while I have far fewer, so his estimate still deserves a lot of respect. I don’t want to overstate the confidence with which I’m stating my forecast. So let me put it this way: My approach says that it’s likely that Obama will outperform the forecasts of poll-based analysts like Silver.

DL: We’ll find out soon enough. Thanks.

Republican presidential candidate Mitt Romney has been strategically slippery about his tax plan, largely refusing to explain how he would pay for the sweeping tax cuts that represent his primary promise to voters.

In the second debate, though, he offered just enough detail for us to sketch the outlines of his program. If you’re poor or worried about the state of the U.S. government’s finances, the picture is not pretty.

The first course in Romney’s plan is dessert: Tax breaks for everyone! He would start by extending the tax cuts put in place by former President George W. Bush. He would then cut everyone’s rates by another 20 percent, repeal the alternative minimum tax, and get rid of the estate tax.

How would he pay for this? Mainly by limiting the amount people can deduct from their taxable income. Here’s the most detailed statement Romney has made: “One way of doing that would be say everybody gets—I’ll pick a number—$25,000 of deductions and credits, and you can decide which ones to use. Your home mortgage interest deduction, charity, child tax credit and so forth, you can use those as part of filling that bucket, if you will, of deductions.”

Big Shortfall

Putting both halves of Romney’s plan together, we compared the impact of the tax cuts with the offsetting effect of limiting itemized deductions. The result: While a cap on deductions is an interesting idea, it couldn’t possibly raise enough revenue to make up for the big tax giveaways Romney has promised. The shortfall would be a whopping $3.7 trillion over the next decade. Lowering the deduction limit to, say, $17,000 wouldn’t much change the math. The gap would still be $3.4 trillion.

Romney’s plan is most striking in its distributional implications (see chart). The greatest benefit would go to the rich. The top one-fifth of households would enjoy a staggering $16,000 average tax cut, offset by a tax increase of $4,000 due to the deduction cap. Net gain: $12,000. Actually, though, most of this group wouldn’t see that large of a benefit. About half of the spoils would go directly to the top 1 percent, which would get an average net tax cut of $100,000 a year.

The further one goes down the income scale, the worse Romney’s plan looks. The average household in the middle of the income distribution—the heart of the middle class—would get a cut of a little more than $800, which wouldn’t be much changed by the limit on deductions. The poor would actually pay slightly more tax, because Romney would end stimulus-related measures—such as an expansion of the Earned Income Tax Credit—that have benefited them.

True, any across-the-board tax cut would give more money to the rich in dollar terms, because they pay most of the taxes in the first place. But Romney’s plan goes further. It would reduce the amount the richest Americans pay relative to their income more than for anyone else. Specifically, the richest fifth would go from paying 26 percent of their income in taxes to 22 percent. The middle fifth would go from 16 percent to 15 percent. The tax burden on the poor would rise.

Romney has explicitly denied that his tax plan would favor the rich: “I will not, under any circumstances, reduce the share that’s being paid by the highest-income taxpayers.”

If this was truly his intention, he could have proposed tax cuts that were proportional to income—say, by offering simply to cut everyone’s tax rates by a few percentage points, rather than by a certain percentage. This would give the rich a bigger tax cut in dollar terms while preserving the distributional structure of our tax system.

Benefit Distribution

As it stands, Romney’s plan would result in 48 percent of the net tax cut going to the richest 1 percent (see pie chart). Another 32 percent would go to the next richest 4 percent of the population. All told, 94 percent of the benefit would go to the top 10 percent of the income distribution, leaving only 6 percent for the rest.

Many of Romney’s biggest boosters argue that he would be a more moderate president than he has been a candidate. Perhaps that’s plausible. On taxes, though, he has left himself little room to maneuver. His constituency would expect him to deliver on the very specific tax cuts he has promised. Meanwhile, his vagueness on the offsetting deduction limits would leave him with no mandate to get rid of the most popular tax breaks, such as those for charitable giving, mortgage interest or health insurance.

Hence, the most probable outcome would be a tax system that is radically less progressive, achieved through cuts that would create a much larger long-run budget deficit. Both outcomes would be colossal failures at a time in which true tax reform is greatly needed.

Event Information

Despite the attention on the mid-term races, few elections are competitive. Electoral competition, already low at the national level, is in decline in state and primary elections as well. Reformers, who point to gerrymandering and a host of other targets for change, argue that improving competition will produce voters who are more interested in elections, better-informed on issues, and more likely to turn out to the polls.

On October 27, the Brookings Institution—in conjunction with the Cato Institute and The Pew Research Center—presented a discussion and a groundbreaking survey exploring the attitudes and opinions of voters in competitive and noncompetitive congressional districts. The survey, part of Pew's regular polling on voter attitudes, was conducted through the weekend of October 21. A series of questions explored the public's perceptions, knowledge, and opinions about electoral competitiveness.

The discussion also explored a publication that addresses the startling lack of competition in our democratic system. The Marketplace of Democracy: Electoral Competition and American Politics (Brookings, 2006), considers the historical development, legal background, and political aspects of a system that is supposed to be responsive and accountable, yet for many is becoming stagnant, self-perpetuating, and tone-deaf. Michael McDonald, editor and Brookings visiting fellow, moderated a discussion among co-editor John Samples, director of the Center for Representative Government at the Cato Institute, and Andrew Kohut and Scott Keeter from The Pew Research Center, who also discussed the survey.

Transcript

• Transcript (.pdf)

Event Materials

• 20061027
• 20061027ppt

On November 7, millions of Americans will exercise their civic duty to vote. At stake will be control of the House and Senate, not to mention the success of individual candidates running for office. President Bush's "stay the course" agenda will either be enabled over the next two years by a Republican Congress or knocked off kilter by a Democratic one.

With so much at stake, it is not surprising that the Pew Research Center found that 51 percent of registered voters have given a lot of thought to this November's election. This is higher than any other recent midterm election, including 44 percent in 1994, the year Republicans took control of the House. If so, turnout should better the 1994 turnout rate among eligible voters of 41 percent.

There is good reason to suspect that despite the high interest, turnout will not exceed 1994. The problem is that a national poll is, well, a national poll, and does not measure attitudes of voters within states and districts.

People vote when there is a reason to do so. Republican and Democratic agendas are in stark contrast on important issues, but voters also need to believe that their vote will matter in deciding who will represent them. It is here that the American electoral system is broken for many voters.

Voters have little choice in most elections. In 1994, Congressional Quarterly called 98 House elections as competitive. Today, they list 51. To put it another way, we are already fairly confident of the winner in nearly 90 percent of House races. Although there is no similar tracking for state legislative offices, we know that the number of elections won by less than 60 percent of the vote has fallen since 1994.

The real damage to the national turnout rate is in the large states of California and New York, which together account for 17 percent of the country's eligible voters. Neither state has a competitive Senate or Governor's election, and few competitive House or state legislative races. Compare to 1994, when Californians participated in competitive Senate and governor races the state's turnout was 5 percentage points above the national rate. The same year New York's competitive governor's race helped boost turnout a point above the national rate.

Lacking stimulation from two of the largest states, turnout boosts will have to come from elsewhere. Texas has an interesting four-way governor's race that might draw from infrequent voters to the polls. Ohio's competitive Senate race and some House races might also draw voters. However, in other large states like Florida, Illinois, Michigan and Pennsylvania, turnout will suffer from largely uncompetitive statewide races.

The national turnout rate will likely be less than 1994 and fall shy of 40 percent. This is not to say that turnout will be poor everywhere. Energized voters in Connecticut get to vote in an interesting Senate race and three of five Connecticut House seats are up for grabs. The problem is that turnout will be localized in these few areas of competition.

The fault is not on the voters; people's lives are busy, and a rational person will abstain when their vote does not matter to the election outcome. The political parties also are sensitive to competition and focus their limited resources where elections are competitive. Television advertising and other mobilizing efforts by campaigns will only be found in competitive races.

The old adage of "build it and they will come" is relevant. All but hardcore sports fans tune out a blowout. Building competitive elections -- and giving voters real choices -- will do much to increase voter turnout in American politics. There are a number of reforms on the table: redistricting to create competitive districts, campaign financing to give candidates equal resources, and even altering the electoral system to fundamentally change how a vote elects representatives. If voters want choice and a government more responsive to their needs, they should consider how these seemingly arcane election procedures have real consequences on motivating them to do the most fundamental democratic action: vote.

Early voting has started in earnest in many states, marking a dramatic change in how Americans vote and how campaigns are run. Preliminary indications are that more people will cast their ballot prior to Election Day than in any campaign in the nation’s history.

Already, well over ten million people have cast their ballot for this November’s much-anticipated presidential election. This statistic is from just a few states and localities where these early voting numbers are available. In Georgia, for instance, more people have already voted early than voted early in all of the last presidential election.

These early numbers are startling, far outpacing what would be expected at this stage in the election. In the past, early voting starts as a trickle, with the spigot opening as the traditional Election Day approaches. These numbers could portend a higher level of early voting, higher overall turnout, or – most likely – both.

The apparent increase witnessed so far is part of the upward trend in early voting that has swept the country over the past two decades. In 1992, about 7 percent of all voters voted early; by 2004 that number exceeded 20 percent. The increase arises among states that have enacted early voting policies permitting people to vote absentee for any reason, to automatically receive an absentee ballot by mail or to vote at special early voting polling place in a high-traffic location.

Those who vote early have changed over the past 20 years. People who vote by traditional absentee ballot tend to be younger, single and highly educated; essentially students, military and professionals traveling on business.

Today, many people tend to be early voters, though early voters are on average older. This age disparity is consistent with the type of person who is motivated to vote early: a strong partisan who is certain of their vote.

Early voters obviously do not show up to vote on Election Day, which causes problems for exit pollsters stationed outside polling places. In 2004, the media’s national exit poll organization conducted phone surveys of early voters to supplement their Election Day polling. These surveys found that in all states – except Iowa – the early electorate was more Republican than the election day electorate, which is an expected pattern steeped in campaign folklore that a Democrat will win if they evenly split the early vote.

The deviating case of Iowa makes sense. In 2004, the Iowa Democratic Party conducted an intense early vote drive, a move that may have cost John Kerry the state since their Election Day ground game suffered.

We are seeing indications that Barack Obama’s campaign is successfully turning out their supporters in Florida, Georgia and North Carolina, three states that provide demographic breakdowns of early voters. In Florida and North Carolina, registered Democrats outnumber Republicans by two to one among early voters. In Georgia and North Carolina, African-Americans are a much greater share of the early electorate than of the overall 2004 electorate. What makes these numbers all the more impressive is not just their disparity towards Democrats, but that we would normally anticipate Democrats to lag behind Republicans at this stage in the game. Do not expect the well-financed Obama campaign to skimp on their Election Day mobilization efforts, either.

It is too soon to tell definitively if these early vote numbers represent a coming flood of early voting and Election Day turnout or if these represent pent up demand by enthusiastic Democrats finally able to cast their ballot. But that this question can even be asked is not encouraging for John McCain.

For McCain to win, he needs to turn the election around – now. The presidency is starting to slip from his grasp. Pre-election polling currently indicates Obama will hold all the states won by Kerry in 2004, plus Iowa and New Mexico. Obama wins the Electoral College if he wins Colorado, a state that he has had a small consistent lead in the polls throughout the year. More than 60 percent of Coloradans will cast their ballot early.

If McCain can not change the campaign dynamic, it will soon be too late for him to shift enough votes into his column to win. He may be able to take one of the states currently favoring Obama, but that will be an increasingly difficult task as ballots pile up in high-early vote battleground states like Florida, Iowa, Nevada, New Mexico, North Carolina, Oregon and Washington.

It’s mid-October. Now is the time for an October surprise, before too many people can no longer be surprised.

View 2008 Early Voting Statistics »

Michael P. McDonald is an associate professor at George Mason University and a non-resident senior fellow at the Brookings Institution. He calculates national turnout rates for academics and the media and he is co-editor of The Marketplace of Democracy: Electoral Competition in American Politics.

With little time remaining until the midterm elections, campaigning is intensifying and the outcome for control of Congress remains uncertain. Voter enthusiasm and turnout will be big factors in the elections, where Republicans have demonstrated a leg up in the party’s primaries.

On October 20, Brookings expert Michael McDonald answered your questions about what the polls and early voting are telling us about the upcoming midterm elections, in a live web chat moderated by POLITICO Assistant Editor Seung Min Kim. McDonald, with Seth McKee, is author of "Revenge of the Moderates," in today's POLITICO.

The transcript of this chat follows:

12:30 Seung Min Kim: Good afternoon, everyone! We have just under two weeks until the Nov. 2 midterm elections, and the Brookings Institution's Michael McDonald is here to answer your questions. Thanks and welcome, Michael.

12:30 [Comment From Dale Dean (Arlington): ] I was wondering from the historical record how closely early results mirror the actual results. Are there systemic distortions in early voting that are the same over many elections or do they differ with each election?

12:30 Michael McDonald: Early voting does not necessarily correspond with Election Day voting. Several data sources suggest the following: Overall, prior to 2008, more Republicans tended to vote early. In 2008, it was Democrats who voted early. We have to see 2010 will be a continuation of 2008 or a reversion to previous elections.

12:30 Michael McDonald: Another important factor is the number of early votes. For high early voting states like Oregon and Washington, essentially ALL votes will be cast early. In other states that require an excuse to vote absentee, the early voting electorate will be much smaller, and have a partisan character more similar to pre-2008.

12:31 [Comment From Katy Steinmetz: ] Are black voters going to turn out for Obama like they did in 2008? Why or why not? How big of a difference do you think this will make?

12:31 Michael McDonald: Since we started surveying, pollsters have found that midterm electorates -- compared to presidential electorates -- tend to be older, wealthier, better educated, and composed of fewer minorities. Sometimes Democrats can overcome this hurdle, as they did in 2006, of course. It would be highly unusual for African-Americans to vote at the same rate as they did in 2008. In some key races, in states with large minority populations, lowered levels of minority voting could be a critical determinant to the outcome.

12:32 [Comment From tim: ] Do the polls accurately reflect the relative turnout of Democrats, GOP and Independents?

12:33 Michael McDonald: Pollsters try as best they can. They try to forecast who is likely to vote by various methods that are not consistent across polling firms. So, this is as much as art as a science. There are a number of factors that may further affect the partisan composition of polls, such as if people are interviewed by live interviewers or automatically or whether or not cell phones are interviewed.

12:34 [Comment From Katy Steinmetz: ] When Republican pundits like Karl Rove predict gains of 60 or so seats in the House, does that help or hurt them (in terms of making Republicans complacent and driving Democrats to the polls)?

12:36 Michael McDonald: One of the big questions in this election is the relative effects of enthusiasm versus voter mobilization. Republicans are hoping the enthusiasm gap will help them to victory, while Democrats are banking on their organization to GOTV. So far as I can tell, neither side has a distinct edge yet.

12:37 [Comment From Casey (DC): ] I have a question about the margin of error. Let's say candidate A has been consistently polling a point above candidate B, with a 3% margin of error. Is the fact that A has beaten B in all recent polls statistically significant, even with a margin of error? That is, wouldn't it be misleading to claim that A and B are tied (due to the margin of error) since A has been beating B consistently in the same poll, even by just a point? If they're truly tied, wouldn't we see A beating B half the time and B beating A the other half??

12:41 Michael McDonald: To quickly review, the MoE is determined by the number of respondents to a survey, and it does not linearly decline as the number of respondents increases [it declines by a factor of 1/sqrt(# of respondents)]. Suppose you have two polls with 1,000 persons each, then. You may treat them as two polls of 2,000. So, the MoE would decline, but it may not decline as much as you might think. Further, as I describe above, different pollsters use different techniques to create likely voter screens (and many other survey issues), so the polls themselves are not entirely comparable.

12:42 Michael McDonald: As a general rule, I like averaging polls and looking at trends among the same pollster. If all the polls are moving in the same direction, I tend to believe that a trend is real and not just statistical noise.

12:43 Michael McDonald: Finally (I know a long answer!): never trust a single poll. Unfortunately, the media tend to report their poll, or a surprising poll, and disregard others.

12:43 [Comment From Jazziette Devereaux (AZ): ] Do you think that early voting can prevent voters from learning facts about candidates that are presented in the feverish last two weeks of the election?

12:44 Michael McDonald: My favorite example is a John Edwards voter who was upset in 2008 that he had cast his vote before he dropped out of the race.

12:46 Michael McDonald: Early voting has certainly changed campaign dynamics. No longer can an opponent release the October surprise the last week. Their opponent gets a chance to respond. And it makes elections more expensive since campaigns need to be active throughout the entire election period. So, there are pluses and minuses.

12:46 [Comment From Mark, Greenbelt: ] Is it your feeling that early voting favors one party over another generally, or is it all case-by-case?

12:48 Michael McDonald: Prior to 2008, more Republicans voted early. In 2010, more Democrats voted early. So, far more Democrats are voting early in 2008, so it may be that 2008 was a watershed election for early voting. Still, in a state-by-state basis, Republicans tend to do better among early voters in states that require an excuse to vote an absentee ballot (early voting rates are much lower, too!).

12:48 [Comment From Rosemarie (NH): ] How do you think negative campaigning impacts turnout?

12:50 Michael McDonald: It used to be that people thought negative campaigning decreased turnout, but since then, numerous studies have shown it increases turnout. People are apt to be interested in slowing down and watching the accident on the side of the road. The media certainly enjoy covering the most negative campaigns, too.

12:50 [Comment From Malcolm, DC: ] Do you have any stats about early voting so far, and can you draw any conclusions?

12:50 Michael McDonald: They are here. So far, over 2 million people have already voted!

12:52 [Comment From Borys Ortega: ] How do you see the Obama support base (liberals, young people, etc) in terms of enthusiasm?

12:52 Seung Min Kim: And in addition to that, it seems like the White House and Democrats are doing a lot more outreach to young voters, with the MTV/BET town halls and the large rallies at universities. Do you think that will have any effect, considering young people have a low turnout rate for midterm elections?

12:53 Michael McDonald: Since we began surveying, polls consistently show that young people, minorities, the poor and uneducated tend to vote at lower rates -- perhaps the most ironic thing about this election is that the people most affected by the economic downturn are the least likely to vote.

12:55 Michael McDonald: The Democrats need to counter the Republican enthusiasm by expanding the electorate. Their strategy is to do voter mobilization targeted at the low propensity midterm voters, like the youth. We will again have to see how effective the Democrat's mobilization will be compared to the Republican's enthusiasm.

12:55 [Comment From Rosemarie (NH): ] Has there been any correlation between the level and campaign spending (especially on advertising) and the results?

12:57 Michael McDonald: A funny statistic is that the more an incumbent spends, the worse they do. This is because they are spending to counter a threat from a viable challenger. This is why this is one of the most difficult questions to answer -- surprisingly. We do not know the marginal effect of another dollar spent because the other campaign is also spending money.

12:57 [Comment From Sally: ] There was a flap this week about Univision airing ads that seek to depress Hispanic voter turnout. How common is that practice?

12:59 Michael McDonald: Voter suppression targeted at minorities has a long and ignoble history in American politics. Generally, I think everyone should vote since democracy works best when its citizens are engaged. This particular episode may ultimately backfire since it may rile up Nevada Latinos in a campaign that has had many racial overtones.

1:00 [Comment From Drew C.: ] What's your evaluation of early vote-by-mail, vs. in-person voting? Are both being done well?

1:00 Michael McDonald: In 2008, approximately 500,000 mail ballots were rejected. These were people who thought they voted by their vote did not count.

1:02 Michael McDonald: Why does this happen? People do not follow the procedures properly -- the return the ballot in the wrong envelope, they do not sign the envelope, etc. I do like California's method of allowing voters to drop their ballots off on election day at their polling places. This allows poll workers to check that the voter followed procedures.

1:03 Michael McDonald: An advantage of in-person early voting is that these problems do not occur, and their is a chance for a voter and election administrators to fix any problems, such as a first time voter forgetting to bring mandatory ID.

1:03 [Comment From Nick, DC: ] Along the lines of what Sally was asking about, we hear a lot about voter suppression, and we also hear a lot about alleged voter fraud. Are either of them really very common? And are voting machines more subject to tampering than the old paper ballots?

1:05 Michael McDonald: Vote fraud -- someone actually intentionally casting an illegal vote -- is extremely rare. When it happens, it tend to happen among mail ballots. Although there are potentially security flaws with electronic machines, there is little evidence of tampering (of course, that may be because there is no way to check!).

1:06 [Comment From Peter G.: ] If you could make one voting reform nationwide to make the system work better, what would it be?

1:08 Michael McDonald: Universal voter registration. There is plenty of evidence that our system of requiring voters to register themselves does not work well. Just about every other advanced democracy registers their own voters. In states with Election Day registration, turnout is much higher (5 to 7 percentage points). So, not only would we increase turnout, but we would get third party organizations like the now-defunct ACORN our of the business of registering voters.

1:09 [Comment From Ben Griffiths: ] You said incumbents fare worse when they spend more. is the same true of challengers? I'm thinking this year of Sharron Angle's $14 million in Nevada. Is it even possible to spend that much in the time left?

1:10 Michael McDonald: The spending in Nevada is tremendous. Despite that likely about half the voters will have already voted by Election Day -- Nevada is a high turnout state -- I think the campaigns will continue spending to the end since the election appears to be going down to the wire.

1:11 Michael McDonald: As for your first question, there is a point where a challenger spends enough money to become viable, which triggers a response in spending from an incumbent.

1:11 [Comment From Rosemarie (NH): ] Is overall turnout higher in states that allow early voting?

1:13 Michael McDonald: I testified to the U.S. Senate that I believe the answer is yes, though the turnout effects are a modest one to two points in presidential elections. There are studies that find big turnout increases in non-presidential elections. Indeed, the very first usage of all-mail ballot elections was in local jurisdictions that needed to meet threshold turnout rates to pass local bond measures.

1:13 [Comment From Nancy: ] Which party gets the early bragging rights?

1:14 Michael McDonald: So far, Democrats have jack rabbited out of the starting line in most states where we have a clue of which party's registrants are voting early. Nevada is an interesting departure, where Democrats have a lead, but it is not as great as 2008.

1:14 [Comment From Carson P.: ] One of your Brookings colleagues - Bill Galston - has proposed the idea of mandatory voting, like they do in Australia. Could that work here? Is it a good idea?

1:15 Michael McDonald: Good luck trying to convince Americans that they will be fined if they do not vote. I do not think this is practical for the U.S., though it obviously increases turnout.

1:15 [Comment From Don: ] What are the prospects for Lisa Murkowski come election day? Do you think she has a realistic shot at beating Joe Miler?

1:16 Michael McDonald: The polls are close. I think it is anyone's game in Alaska. In fact, I wrote an op-ed with my co-author Seth McKee, which was published at Politico today.

1:16 [Comment From Greg Dworkin: ] Thanks for all your hard work on this! How 'institutionalized' do you see the early vote by the parties? are they incorporating early voting as part of GOTV or are they behind in realizing so many people vote early these days?

1:19 Michael McDonald: As I document with another co-author -- Tom Schaller -- the Democrats created a strong early voting GOTV organization in 2008, and Republicans only belatedly tried to mobilize their voters to vote early. We will have to see how well Democrats will roll over this organization to 2010. Eventually, I believe the Republicans will have to build as strong as an organization. Early voting allows a party to mobilize over a longer period of time.

1:19 [Comment From Mary H. Hager, PhD: ] Please clarify polling methodology. Who is reached; who is not. The role of technology (email, telephonic, etc.) in defining the subpopulation for polling data.

1:20 Michael McDonald: That is quite a tall order for a chat :) We discuss many of these issues on Pollster -- which now has a home in the politics section of Huffington Post (I also blog at Pollster).

1:21 [Comment From Don (Ossning, NY): ] Does Christine O'Donnell have a chance in Delaware?

1:21 Michael McDonald: No.

1:21 [Comment From Geoffrey V.: ] Over the years, I've gotten the sense that campaigns are moving faster, that there are more undecided voters and that many voters don't make up their minds until the last minute. Is that supported by the data?

1:23 Michael McDonald: Well, given the tremendous increase of early voting from 20% in 2004 to 30% in 2008, it appears that many voters are making up their minds sooner, not later. Still, in a midterm election, the rule has generally been that people tend to hold their ballots longer because they do not have as much information about the candidates. It appears that this election may break that previous pattern.

1:23 [Comment From Joan: ] Do you think compromise will come back to Congress after the midterms?

1:24 Michael McDonald: No. Historically, we still have a ways to go before we reach the highest levels of polarization in our politics observed in the late 19th century.

1:24 [Comment From Al Amundson, ND: ] It seems sometimes that pollsters are "surprised" by wins. Polling is so scientific these days, and there's so much money behind it -- how often does a real surprise actually occur?

1:25 Michael McDonald: Surprises more often occur in primary elections, where the electorate is difficult to predict and information is fluid. I do not expect we will be greatly surprised by the 2010 election outcomes.

1:25 [Comment From Rosemarie (NH): ] Do you think that even with early voting, people just want to get it over with, go in to vote and make up their minds while they read the ballot?

1:27 Michael McDonald: Want the campaigns to stop bugging you? Vote early if you can. Election officials track who has a mail ballot in hand and who has voted, and they share this information with the campaigns.

1:27 [Comment From Bert C.: ] How is Sharron Angle still holding on in Nevada even after her numerous public gaffes?

1:27 Michael McDonald: The economic crisis has hit Nevada VERY hard (and I don't often write in caps!).

1:28 [Comment From Peggy: ] What role do you think the Tea Party will play in future elections? Is this a one-off movement or something more serious in American politics?

1:30 Michael McDonald: Shameless plug: see my Politico op-ed. A conservative/populist movement is nothing new to American politics. At least in the short run, I expect the tea party to continue to be influential, especially if Republicans take the House -- I do not expect they will take the Senate as of today. Victories will further embolden the activists.

1:31 Michael McDonald: Thanks to everyone for your questions. Sorry I could not answer them all!

1:31 Seung Min Kim: And that's it for today. Thanks for all the great questions as we count down the days until Election Day. And thanks to Michael for his insightful answers!