A new PPP poll for the Daily Kos and SEIU shows Mitt Romney with a two-point lead over President Obama.

Dennis Van Tine/Retna Ltd/Corbis

or weeks this fall, conservatives complained that opinion polls were rigged against Mitt Romney. Pollsters, they said, were over-sampling Democrats, giving voters the fall sense that President Obama is more popular than he really is. Now, though, Romney is surging in the aftermath of his big win in last week's debate, with multiple surveys indicating that the GOP challenger has caught up with — or even surpassed — Obama. A new Pew Research poll puts Romney four percentage points ahead nationally. Does that prove the polls weren't biased in the first place, or does it raise even more questions about their accuracy?

The latest polls are unfair... to Obama: Pew has "irreproachable credentials," says Nate Cohn at The New Republic, but the swing in its last two polls — from an eight point Obama lead before the debate to a four point Romney lead after — is "not especially plausible." In Pew's latest survey, there were more Republicans than Democrats in the sample. Maybe conservatives who screamed "party ID!" should now argue the polls are biased in Romney's favor.
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But party ID has nothing to do with bias: There's a simple explanation for Romney's big leap in the polls, says Jon Cohen at The Washington Post. Pew and Gallup found more people identifying themselves as Republicans because, for now, more voters have warmed to the GOP. Fence-sitters "showed a clear Democratic tilt" when Romney was fighting his "47 percent" gaffe, and his debate performance has more of them embracing the GOP. That's not a sign of bias, just shifting opinions.
"How party ID explains Romney's 'surge'"

And clearly, Romney's bounce is real: We shouldn't focus too much on any single poll, says Matt Vespa at Hot Air. The only thing that matters is that, taken together, the surveys indicate pretty clearly that Romney's trouncing of Obama showed voters that "Mitt is energetic, hungry, and won't back down in framing the president as anathema to American enterprise." Even low-information voters saw that Mitt's not the job killer, dog abuser, and tax evader that Democrats caricature him as, and as a result, they're lining up behind him.
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Read more political coverage at The Week's 2012 Election Center.