But the CNN survey also historically correlates fairly well with movement in the post-election polls. Below, you’ll find a comparison between the perceived winner of the CNN/Gallup poll in debates since 1984, and how much the horse-race polls changed afterward. In 2012, for instance, Romney gained a net of 4.4 percentage points on Obama, although he eventually lost most of those gains. Bill Clinton, meanwhile, saw the polls swing by 4.1 points in his favor after the town hall debate of 1992…

But there are several other reasons to think Clinton could get a bounce, and perhaps a relatively meaningful one. In addition to the polls, a variety of post-debate indicators implied a Clinton win, including focus groups, betting markets, and the post-debate coverage on television networks. The TV coverage matters because the pundits’ reaction doesn’t always match that of voters in instant polls, and it’s sometimes the TV spin that wins out. Voters narrowly scored the first presidential debate of 2000 as a win for Al Gore, for instance, but after intense media focus on Gore’s demeanor, it was George W. Bush who eventually gained ground in polls.

This time, pundits and pollsters seem to agree on the Clinton win. It’s certainly possible that by the time you’re reading this — I’m writing at 3 a.m. — some storyline that cuts against Clinton (and which didn’t seem like a big deal on Monday night) will have emerged. But the correlation between the instant-reaction polls and the eventual effect on horse-race polls has actually grown stronger in recent election cycles, perhaps because the conventional wisdom formulates itself more quickly.