Democracy Corps has a particularly cogent analysis of last nights debate. The overview follows:

John McCain entered tonight’s debate needing to halt Barack Obama’s momentum and fundamentally change the dynamic of the race. Not only did he fail to achieve this goal, McCain dug himself an even deeper hole.Undecided voters watching the debate felt McCain gave a decidedly un-presidential performance, appearing rude, negative, and easily flustered – a stark contrast to Barack Obama’s cool, commanding presence. Obama was seen as the clear victor in the debate, and a group that was much more disposed to support McCain at the outset instead shifted decisively toward Obama (42 to 20 percent) after viewing the debate.

Democracy Corps conducted dial and focus groups with 50 undecided voters in Denver, CO during and after tonight’s debate. Prior to the debate, these undecided voters had an unmistakable lean toward McCain, giving him strong personal marks (54 percent favorable, 34 percent unfavorable) while dividing evenly on Obama (42 percent favorable, 42 percent unfavorable). In fact, in the focus groups conducted after the debate, many of these voters explicitly said that they came into the evening wanting to vote for McCain.But the debate changed their outlook significantly. By a 50 to 24 percent margin, these voters said that Obama won the debate. More significantly, the debate moved their vote considerably, with 42 percent supporting Obama and 20 percent supporting McCain.This was the most decisive movement we saw toward Obama in any of the three debates.
McCain only had himself to blame for much of this movement.His attempts to attack Obama fell completely flat, failing to move the dials against Obama and often backfiring instead.McCain’s harsh tone, dismissive body language, and many interruptions turned off these voters. McCain’s personal favorability actually declined over the course of the debate, the first time we have seen that for either candidate during any of the three presidential debates. Our focus groups showed that McCain’s performance raised serious questions about his temperament and age, with many respondents shocked at how easily he seemed to lose his composure and a few dismissing him as “a grumpy old man.”
Meanwhile, McCain failed to make progress toward his central goals of defining Obama as a big-taxing liberal. The proportion of these voters who saw Obama as “too liberal” declined by 8 points during the debate and, in a head-to-head matchup with McCain, Obama actually gained 10 points on who would do a better job with taxes. McCain’s attempt to tie Obama to William Ayers and ACORN fell flat, resulting in negative scores in the dial test and drawing rebukes in the focus groups following the debate.
While McCain lost personal standing, Obama made impressive gains, moving from an initial favorability rating of 42 percent warm, 42 percent cool to 72 percent warm and 22 percent cool – an impressive net gain of 50 points. More importantly, Obama made gains on the threshold questions of his fitness to be president. Before the debate, just 38 percent of these voters said he “has what it takes to be president,” but by the end of the night, this had increased to 56 percent. The Democratic nominee made a similar 18-point gain on “can trust him to make the right decisions.”These results were underscored by our focus groups, where voters said Obama came off as reasoned, collected, and presidential.
In addition to beating back McCain’s effort to pain him as a liberal, Obama made significant progress reassuring these voters that he shared their values. Two of Obama’s best moments came when he discussed the need to bring all sides of the abortion debate together to help reduce unwanted pregnancies and when he ended his discussion of education policy with a call for parents to take more personal responsibility in how they raise their children. Both responses earned strong scores on our dials and helped Obama turn what was an even draw (30 percent each) on who best “shares your values” before the debate to an impressive 50 to 26 percent advantage afterwards.
Because Obama was preferred over McCan by a 2-to-1 margin after the debate, we conducted two follow-up focus groups among previously undecided voters who shifted toward Obama, divided by gender. The women saw a clear victory for Obama that was more about temperament and character.They derided McCain’s performance as ‘rude,’ ‘disrespectful,’ ‘immature,’ and above all else ‘negative. ’They were frustrated by his eye rolls, likened his verbal miscues and mispronounced words to President Bush, and criticized his constant interruptions of Obama. By comparison, Obama was seen by these women as organized, direct in his answers, and very deliberate in his thought process and responses to McCain’s aggressive challenges. In short, he was seen as presidential. But Obama also impressed them with his answers on health care – the issue where they saw the clearest distinction between the candidates – as well as taxes, education, and the Supreme Court.
The men who shifted toward Obama came into the debate predisposed to support McCain, but they were terribly disappointed in the Arizona Senator’s performance. They felt he had nothing to say about himself, his plans, or the country’s future.His answers were scattered, and he simply resorted to angry attacks that were disconnected from the country’s priorities. But more than anything, these men were also turned off by McCain’s behavior during the debate, when they quite simply felt he came across as “a jerk.”Several of the men commented on McCain’s age, describing him as a “grumpy old man,” whose choice of running mate demonstrated terrible judgment, particularly given his age and the possibility of his Vice President needing to replace him in office. Just as with the women, Obama also passed key thresholds with these voters and provided valuable reassurance on the many doubts they brought with them into the debate. They felt Obama offered strong answers with precise plans on the key questions and issues raised in the debate, and they were particularly reassured by his mention of a strong team that showed he would have “good people” around him.
Tonight’s final debate has reinforced the narrative of this campaign rather than shifting it and made it more difficult for McCain to reverse the current course.McCain raised more questions about his candidacy rather than Obama’s, while Obama further reassured undecided voters on key questions of his ability to handle the challenges facing the country.