This shouldn't even be controversial, but of course it is. Partly that's because it's news some people don't want to hear. But I think there's also a math-is-hard problem: a political universe in which there are lots and lots of polls seems to play into some natural failings of our mathematical intuition.

First of all, from what I can see a lot of people have trouble with the distinction between probabilities and vote margins. They think that when I say, "state level polls overwhelmingly suggest an Obama victory", I'm also saying "state level polls suggest an overwhelming Obama victory", which isn't at all the same thing. We have a lot of polls, almost all of which say that Obama will win Ohio; but they don't by any means say that he'll win it in a landslide.

Second, people clearly have a problem with randomness -- with the fact that any poll, no matter how carefully conducted, has a margin of error. (And the true margins of error are surely larger than the statistical measure always reported, since sampling error isn't the only way a poll can go wrong). Specifically, what I think people don't get is the fact that when there are many polls of a state, some of them are bound to be outliers -- not, or not necessarily, because the pollsters have done a bad job, but because there's always noise in any sampling procedure.

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Oh, and a third point: those margins of error are for any one poll. An average of many polls will have a much smaller standard error. Don't say, hey, Obama may have a three-point lead, but that's within the margin of error; as Pollster points out, the odds that this is a true Obama lead are 99 percent.