Barack Obama

Overcame his pre-debate head cold and spoke firmly on national security, but created little explicit contrast with the frontrunner, except for one elbow thrown Clinton's way on her health care record. Cool, smart, likeable, and on message on Iraq, health care, and change — but at times a little shaky and tentative. Far from dominating the stage, he seemed to disappear for long stretches. Some forward progress — but not much.

—By Mark Halperin