I'll point out two pretty good pieces debunking "comeback" talk -- one from Brian Beutler, who emphasizes that getting some comparatively easy stuff done in the lame duck session doesn't really change the math in the 112 Congress, and one from Jay Cost, who is absolutely correct to characterize Barack Obama's approval ratings as flat, not surging.
Although I will note that since Cost wrote, Obama has slipped up to 49% per Gallup -- so there might be a bit of a bounce. Or perhaps just some positive random variation.
But mainly, I think both are correct. Some success in the lame duck session isn't going to have a major effect on Obama's approval rating over time, and come the new year, we'll have a new Congress and a lot more Republicans, and that will have real consequences, regardless of how the December spin war goes.
What does strike me, however, is the big dog that didn't bark: the Democrats, from Obama to the Hill to (near as I can tell) most bloggers, talk show hosts, and activists...they didn't panic. Despite a devastating loss in the midterms, Democrats did not for the most part convince themselves that they were destined to be a minor party, did not for the most part declare factional war, did not for the most part attack the president, the Speaker, or the Majority Leader. Certainly, both Harry Reid and Nancy Pelosi easily survived any potential challenges.
Moreover, as far as I can see, the neutral press mostly went along.
In all, it was a sharp contrast with 1994, when the Democrats moved straight to fatalism and despair. Indeed, it was a big of a contrast with winter 20092010, when Democrats seemed to expect themselves to panic and self-immolate after the Massachusetts Senate race.
Granted, this is mostly impressions and speculation, but I suspect that those who remember 1994 and were paying attention then and now would agree.
Why? I suspect a large part of it is just the pattern. If I had to describe what's happened (and again, this is all speculative, I admit), Democrats in 2008 began by thinking "This Is It! This time is going to be different!" By August 2009, and then through January 2010, that attitude was replaced with "It's Clinton all over again." So the election disaster was already factored in by January 2010, but the legislative victories, beginning with health care reform, were basically pleasant surprises. And now, Democrats believe they've seen this film before; a midterm landslide is supposed to be the prelude to comfortable reelection, even if it doesn't yield a newly favorable policy environment.
Of course, even if I'm correct about all that, it doesn't necessarily mean it played a major role in getting things passed in the lame duck session; a lot of that was just about having the votes, and being willing to cut deals when they were available. Still, the Democrats certainly could have tried to do less, so I think there may be at least a bit of something to explain, and I'll go with the favorable side of the Clinton pattern as, perhaps, a bit of what happened.