It all depends on where you set the bar. Biden went in with the huge advantages of a Washington insider. For thirty years his life has centered on national politics. He has lived the ongoing policy debates of our government for three decades. Further, he has multiple presidential debates under his belt. Palin entered national politics less than two months ago and has only debated on a state level.
If we are measuring clarity of response to the specific questions asked and cogency of argument, I think Biden gave the better performance. He showed uncharacteristic restraint in his responses. He addressed the issues as presented and responded to Palin’s charges. Palin had a tendency to divert questions back to her key issues in ways that ignored important aspects of the topics. While it is strength to be able to logically tie issues together, if the connections are not clear it appears the speaker is trying to skirt the issue. She did an good job of presenting her core arguments, but at times seemed off topic.
If we are measuring the more ambiguous specter of personal presence, I think Biden also won. He did a better job of presenting himself as Presidential. In the face of national fear over the economy, he looked and spoke like a competent CEO. Palin, while looking competent, professional, and relaxed, came across as too folksy to demand the same level of respect as a leader in a time of crises.
If we are measuring validity and veracity, I think Palin won the evening. She was true to her message and that of McCain, making points that she knew are highly unpopular (for example, defending aspects of the war in Iraq). She came with clear set of criticisms of Obama. As for Biden, he got a lot of facts wrong, facts that he should as an insider have gotten right (for example, an erroneous correction of Palin about the Obama/McCain voting record). But he presented them with such confidence they appeared accurate. He had the burden of living with his own sharp criticisms of Obama during the debate and the best he could do was ignore those about faces each time Palin brought them up. She was not free from error or political spin but her statements were consistently grounded in conviction.
If we are measuring political strategy for the event, I think it was a tie leaning in Palin’s direction. She came in the underdog and did an outstanding job renewing her convention persona and thereby reconnecting with the conservative public (especially the Republican base which was desperate for a sign). She was cogent, articulate, personable, and consistently conservative. She threaded the gay rights issue well enough while stressing her personal convictions and renewing her commitment to traditional marriage. In short, she reversed the negative slide projecting herself as a positive force (not a drag) on the ticket. Biden was constrained, articulate and on message. He did not create problems for his ticket. Neither bloodied the nose of the opposing ticket much less deliver a knockout blow.
Although I don’t think I have written it before today, I have always said this race is the Democrats to lose. We have an unpopular Republican President, an unpopular war, and a struggling economy. So far they have not fumbled the ball.
Consider http://www.youtube.com/watch?v=vaG6s05MKeM and