UPDATE: It turns out that CNN's poll was, shall we say, not representative of reality. CNN notes that 37% of respondents were Democrat and 33% were Republican, but as a commenter points out, a closer look shows that none of the respondents were under 50; all of them were white; all of them were from the South.
While both sides quickly mobilized online to point out inaccuracies by their opponent (with a post by the president's "Truth Team" and a post on GOP.com titled "Fact Checking Obama"), presentation probably carried the day. Mr. Obama seemed to be playing defense throughout much of the debate, speaking haltingly in some instances, while Mr. Romney was consistently both eager and fluid.
Judging from the response on social media, stagecraft seems to have been a significant factor in Mr. Romney's perceived advantage over the president. Pundits from both sides of the political divide noted that while Mr. Romney watched Mr. Obama intently on the split-screen view as the president was talking, Mr. Obama looked downward and jotted down notes when it was his opponent's turn to speak.
HBO's Bill Maher (who donated $1 million to a pro-Obama Super PAC earlier in the year) tweeted, "Barry: less looking down making notes (u look like you're hanging your head in shame) and more eye contact. Look at Mitt like he's a nut!" Meanwhile, George W. Bush-press-secretary-turned-CNN-talking-head Ari Fleischer tweeted, "It's a mistake for O to look away from Romney when R attacks. O should look him in the eye."