Illinois Senator Barack Obama
Had the audience on his side from the beginning, reflecting his strength in the state and among the African-American groups who co-sponsored the debate. Went in prepared to be tough — and ready to unleash his frustrations after several unnerving weeks of intense Clinton-Clinton double team attacks — but was repeatedly thrown off by Senator Clinton (with the occasional assist from Senator Edwards), who discharged a series of pointed accusations (his words of praise for Reagan; his "present" votes as a state legislator). Nevertheless, seemed willing (or at least resigned) to battling both Clintons. Chose to abandon the politics of hope for "new" politics, apparently out of necessity, but it muddled his focus. While he made some strong points, he was often on the defensive.
Bottom line: Despite some weak debate moments, he is likely to get good coverage in South Carolina, which is next up and thus essential to him.
—By Mark Halperin