The Bradley Effect? Fuggedaboutit.

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Or so says FiveThirtyEight's Nate Silver--who, as I reported earlier this cycle, has a pretty impressive track record when it comes to predicting election outcomes. As Silver writes in an exclusive analysis, John McCain and the GOP shouldn't count on the polls overestimating Obama's level of support: "examples like Bradley and Wilder are nearly a quarter of a century old, and there's no proof that the Bradley effect still exists." A key excerpt:

Everyone remembers New Hampshire, when nearly all polls predicted a big win for Obama, but Hillary Clinton emerged victorious...What fewer remember is what happened two weeks later in South Carolina. In that case, the Pollster projection had Obama winning by 15 points—but he won by 29. That 14-point error was actually of greater magnitude than the mistake in New Hampshire, if less noticeable because the polls hadn't picked the wrong horse.

South Carolina was not the only state in which Obama overperformed his polls. They significantly underestimated Obama's margin in essentially every Southern state, including Virginia, Georgia and North Carolina, as well as a couple of states outside the South, like Wisconsin, Indiana and Oregon. On balance, the polling during the primaries underestimated Obama's support by 3.3 points when compared to the Pollster averages in those states. And yet, a belief in the Bradley effect persists. Why? People are confusing voters exhibiting racist behavior with voters lying about their intentions to pollsters.

There is little doubt Obama is losing some votes due to his race; a recent Associated Press survey suggested that as many as 6 percent of the electorate may be voting against Obama because he is black. But that's not what the Bradley effect is about. As long as those prejudiced voters are telling pollsters that they're going to vote for McCain, their sentiments will be reflected accurately in the polling. The Bradley effect emerges when voters tell pollsters one thing and then do another at the ballot booth.

So the question is why, if a voter does not intend to vote for Obama, would he or she feel compelled to lie about it? There are perfectly legitimate reasons not to vote for Obama; a voter who wanted to vote against him because of his race would have little trouble rationalizing his vote. If a voter felt compelled to lie to a pollster, he might tell them that he was voting against Obama because of his inexperience or his liberal politics—when, in fact, he was voting against him because of his race. But the pollster would still tally the vote correctly in the McCain column. By contrast, in cases where the Bradley effect existed, including Bradley's race itself, the black candidate was as much or more experienced than the white opponent. So voters found it harder to excuse their racism and may have misstated their voting intention to pollsters as a result...
With so many "X factors" like race, cell phones and turnout, there is probably an extra margin of error this year. And polls aren't terrifically accurate to begin with. But there is no reason to conclude that the polls are systematically overestimating Obama's support; the reverse is at least as likely to be true. McCain, in all likelihood, will need to win this election fair and square—which means that he has his work cut out for him.