From NBC's Chuck Todd
Giuliani and McCain looked and acted like the frontrunners tonight. They got opportunities to look presidential and seized the moments. Romney, after a great first debate, turned in a very mediocre performance. Part of his problem were the surprisingly tough questions he received from his inquisitors which seemed to throw him off. But there was something about him that just seemed less present on stage tonight. Maybe it was because he wasn't standing on the far left side of the stage, like McCain this time and Romney was in the first debate.
As for the rest of the field: Huckabee turned in another solid performance. Why again can't he catch financial fire? Tancredo also seemed to improve from his first performance. He actually had a few prepared lines and delivered them fairly well. Paul, as usual, was very eloquent in his positions; nobody has articulated the Libertarian positions as well as him in the GOP for a long time. Hunter, Thompson and Gilmore didn't seem on their games tonight. For Hunter, that's a change; he had a very good first debate; Thompson technically improved from his first performance but that's not saying much. Gilmore was a big part of this debate but his failure to stand behind his campaign trail attacks was a very weak moment for him.