We talked the other day about poll denialism, and the notion, widely embraced among Republicans, that all major-outlet polls have been skewed as part of a conspiracy to boost President Obama over Mitt Romney. It’s a pretty silly argument, but it’s hard to avoid.
And while it’s easy to mock those who feel the need to create their own reality, there was one aspect of conservatives’ complaints that seemed more plausible than the rest: it’s a mistake for pollsters to rely on the 2008 turnout model.
As the argument goes, the political landscape has changed quite a bit over the last four years, so there’s no reason to assume the electorate will be nearly identical. To rely on a turnout model that’s bound to be different necessarily leads to “skewed” results.
Sounds reasonable, right? The problem, though, is simple: as Nate Cohn explained, major pollsters aren’t relying on the 2008 turnout model.
Most pollsters don’t weight their polls to match a preconceived electorate. Instead, they take a demographically representative sample based on actual figures from the US census and then let respondents speak for themselves about whether they’re voting for Obama or Romney. For illustrative purposes, consider the Bloomberg/Selzer poll. They started by taking a sample of all American adults, weighted to match the demographics of all adults in the US census, like, race, education, and marital status. To produce a likely voter sample, they then would have excluded adults who weren’t registered to vote and then asked a series of questions to help determine who was likely to vote.









