Politics & Policy

Much Ado about Polling

A guide to why polls can change so much.

Everywhere I went Monday, conservatives were spooked by a Gallup poll showing President Obama with a six-point lead over Mitt Romney. Then on Tuesday, a Washington Post/ABC News poll had the margin down to a single-point Obama edge. What is going on?

As Election Day draws closer, most major public-opinion surveys shift from interviewing registered voters to interviewing those whom they identify as “likely voters.” The transition from polling “registered voters” to predicting who will actually vote is a tricky one and can involve some turbulence and differences between pollsters. Furthermore, some organizations make the switch earlier than others — in the case of this week’s polls, Gallup’s was of registered voters, the WP/ABC one was of likely voters. And that could have made the difference.

As Nate Silver, the statistics guru of the New York Times, reports, “In the past six presidential election years, the shift to likely voter models has always helped the Republican candidate, but the difference has also always been small.” Pollster Scott Rasmussen argued during the 2010 elections that his polls, which always interview only those voters he determines are most likely to vote, are more accurate. This group, he says, is trending more conservative these days because opponents of Obama’s policies are highly motivated  to vote. Pollster John Zogby says polls tend to oversample Democrats, especially blue-collar women, who often don’t vote. Thus, “the results may be skewed toward the Democrats.” 

Complicating the search for likely voters is the fact that people like to tell pollsters they plan to fulfill their civic duty and vote. A typical September poll will find three-quarters of registered voters saying they plan to vote in November. In reality, about a third of those won’t show up. Pollsters try to determine who will make up the actual electorate by asking people if they know when Election Day is, if they watched any of the debates, or if they have filled out their sample ballot.

Another factor this year may be an “enthusiasm gap” working against Barack Obama. Such a gap is hard to measure, but when pollsters fail to sufficiently take account of it, they tend to undersample one side and oversample the other. Take a CNN/ORC International poll released September 10 that found likely voters supporting the president over Romney by 52 percent to 46 percent. The sample was massively skewed toward Democrats, who made up 50.4 percent of those surveyed while Republicans and independents accounted for only 45.4 percent and 4.2 percent respectively.

Another factor could be the “bounce” Obama got from the Democratic convention, which fueled interest in voting among his base. The Washington Post/ABC poll found that “strong enthusiasm” among Obama supporters was up eight points after the convention.

That interest might be permanent or it could be very fleeting. We just don’t know.

Certainly, on-the-ground workers for Obama are aware that enthusiasm for their man has diminished. Bob Fulkerson, co-founder of the Progressive Leadership Alliance of Nevada, told a reporter from the New Zealand Herald: “He was a knight in shining armor. Four years later? Okay, there is some disappointment. We still have to fight like hell to get this guy reelected.”

Another explanation for why polls differ so much lies in how they handle the “undecided” voter.

This year there may be more undecided voters out there than people think. Most pollsters deal with voters who say they “don’t know” how they will vote by asking them whom they lean toward. Zogby says that kind of “hard pushing” creates very “soft” supporters, who can easily change their minds or not vote at all.

There are other reasons polls tilt slightly toward Democrats. The late Warren Mitofsky, who developed exit polling for CBS News in the 1960s, believed Democrats were more likely to respond to media polls than were Republicans, who may distrust the “liberal” news media. More than 80 percent of the people pollsters try to contact routinely hide behind voice mail or screening devices or otherwise refuse to answer. That makes survey results more uncertain, and should cause concern, caution, and above all humility in reporting polling results.

Having said that, there is something approaching a firm rule of polling in modern presidential politics: If an incumbent president has an approval rating of below 50 percent in September of an election year, he will not be reelected. George W. Bush escaped that fate in 2004, when his approval rating ticked up from 48 percent in August to 52 percent in September. He won with only 51 percent of the vote.

Obama’s approval rating among registered voters is still underwater and didn’t budge much after the Democratic convention in most polls. In the Washington Post/ABC poll he is at 48 percent approval. He has consistently lacked majority approval from voters for two and a half years.

Voters surveyed by the Washington Post also have an ambivalent view of Mitt Romney, with 49 percent saying they are “very” or “somewhat” confident he could turn the economy around in “the next year or two,” compared with 46 percent who say the same for Obama. A full 36 percent are “not confident at all” that Obama will get the economy to improve if he is reelected. That level of skepticism remains a tough hurdle for an incumbent to overcome.

And, finally, one reason no one should count Mitt Romney out is that his views still fit the temper of the times better than Obama’s do. In the Washington Post/ABC poll, registered voters say by 53 percent to 40 percent that government programs do more to interfere with people’s lives than to improve them. That’s why, should Obama lose, it may be things such as Obamacare, Solyndra, and wasteful stimulus spending that sealed his fate just as much as the weak economy.

— John Fund is national-affairs columnist for NRO.


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