From best to worst, based on who did the most to further their chances to win the nomination:
1. Mitt Romney. HUGE night for him, and he hit it out of the park. He killed Perry, and for him that counts more than anything else.
2. Herman Cain. His best night so far. In fact, he's been improving dramatically with every debate. He came out of nowhere -- the only real "outsider", who has never held political office, and now he's competitive with any candidate on that stage, and did better than anyone except Romney. No surprise if he surges in the polls after tonight.
3. Gary Johnson. Being the low man on the totem pole, he got shafted with time. But crowd reaction to him was great, and he had the most memorable line of the night. I don't think I've ever laughed so hard at a presidential debate. He came across as a serious, and in my opinion far better, libertarian alternative to Ron Paul. The other networks did our country a great disservice by not including him in the previous debates.
4. Michelle Bachmann. She did very well tonight. Every answer was on target and well thought-out. And she didn't claim that vaccines cause mental retardation. Her best performance yet. She's a serious candidate but still hurt by her lack of executive experience.
5. Rick Santorum. Maybe just because he was given disproportionate time relative to his position in the polls. His attacks against Romney were hard and effective. As were his attacks against Huntsman. He is a consistently good debater, though he gets too emotional at times. His fumbling answer on DADT was a low point. He had a rehearsed answer, and when the moderators threw him a curve ball, he stumbled big time.
6. Ron Paul. He did relatively well in this debate. No gaffes -- or perceived gaffes, I should say, since he means everything he says 100%. But he did a good job explaining his hard libertarian positions, at least better than he usually does given the limitation to short sound-bites.
7. Newt Gingrich. He's the smartest guy on the stage, and always comes across that way. Nobody dares attack him, and it is beneath him to attack anyone. Every answer is close to perfection, but he sounds academic. Like he's the teacher and the other candidates his students, and his responses sound more like he's giving his opponents advice, rather than trying to win it himself. Newt would make a great President, but I think his destiny lies elsewhere.
8. Jon Huntsman. He basically rehashed his performance from the last debate, when he needed to step up his game big time. He looks presidential. He sounds presidential. He has some good policy positions. But his answers seem to lack substance, and his "America's core is rotten" line was effectively eviscerated by Santorum. Maybe he's coming across as too much of a politician to gain significant support in this election cycle.
9. Who am I forgetting? Oh yeah, Rick Perry. He did not do well at all. In fact, he was forgettable. The attacks against him were more memorable than his responses. His answer on Pakistan made no sense. His answer on Social Security made no sense. He was the only candidate without a specific economic plan, and he admitted it! His answers all boiled down to "look what I did in Texas". Yeah but man, you're not running for Governor of Texas anymore; you're running for President of the USA. That crap is not going to cut it. He's not ready for the big leagues.