It was clear to anyone watching, I think, that Romney "won" the first debate. The question is, does it matter?
Since televised debates began, only one sitting president was said to have won the first debate with his challenger. So even before the debate, there were several stories about how debates don't matter, that historically they don't seem to actually affect how people vote. I'm not so sure of that, but there's some interesting evidence from this debate that supports it – focus groups.
A blog called No More Mister Nice Blog has this round-up:
* Priorities USA's Colorado focus group of "weak Democrats and independents who voted for Obama in 2008 but who remain open to switching" thought Romney wasn't specific last night; they warmed somewhat to his tax ideas, but "there was a doubling in the number of respondents who said that Obama has good ideas for improving the economy.... 63% of respondents said at the end that Obama expressed good ideas for improving the economy, compared with 27% who said the same about Romney...."Feel better now?
* In a focus group of independents on MSNBC, not one switched to Romney after the debate. (Hat tip: Never Ben Better in comments.)
* In another Colorado focus group of undecideds assembled by pollster Stan Greenberg, Romney gained somewhat -- 27% leaned his way before the debate, 44% afterward. But Obama held his ground -- 30% or 31% before (the link is ambiguous), 33% afterward. I read that as a 15-point swing -- but translated nationwide, it suggests that, if something like 5% of voters are undecided, Romney's getting less than a 1% gain. And that's in the immediate afterglow of the debate, which will wear off by Election Day.
* Oh, and if you believe this sort of thing is meaningful, Twitter comments about Romney leaned extremely negative last night, while comments about Obama leaned positive.
Beyond that, Obama had built up a bigger cushion than we thought before the debate: Gallup shows him up by 4 over Romney today (that's averaged over the seven pre-debate days), while his approval rating (over the three pre-debate days) has leaped to 54 percent.