Tonight was the opening salvo in the fight for the large number of undecided voters in Iowa. I suspect that people who don't have a candidate yet are probably more to the left, because Hillary has a strong hold on moderate Dems, and Obama appeals to moderates as well.
CLINTON - Not a superb performance, but good enough, so she's the big winner because she did enough to flip the script to the "come-back" narrative. Will re-inforce her front-runner status and reassure any wavering in her best demographics.
KUCINICH - A big winner because he gave some left-leaning undecideds some passion to draw their vote. IMPEACH NOW!
BIDEN - Best night yet. Should be worth about 3 points in Iowa... maybe more. His mention of Impeachment is a big deal, coming from a 'mainstream' guy.
EDWARDS - Very mixed. Probably alienated some of his moderate support, but drew some left-leaning and economically distressed undecideds. Most people he pissed off probably weren't going to vote for him anyway. I think Edwards had some momentum in Iowa going into this, and this debate should help because there's a hunger from leadership from the left in this field. (Current undecideds are probably more progressives than moderates)
OBAMA - Steady performance, and much better than Edwards. I only have him this low because I think that the progressive vote is up for grabs, and Edwards and Kucinich (and even Biden) did a better job of grabbing it. Nothing that would threaten his #2 position. The immigration ramble will get play just as tit-for-tat with the Hillary thing. Some very good answers. On balance, no particular help or harm. (Probably had the most supporters in the audience. Good crowd response.)
DODD - I like Dodd, but he would have had to turn water into wine to get attention tonight.
RICHARDSON - Again, I like Richardson, but he was just weird tonight. Some fine answers, but too much weirdness & rambling.