If President Obama's first debate did nothing else, it sure lowered expectations for his performance in the second debate. Cue Pew:

On the eve of Tuesday night’s second presidential debate at Hofstra University, voters are divided as to which candidate they think will do the better job: 41% say Obama will do better, while 37% expect Romney to prevail. This stands in stark contrast to expectations prior to the first presidential debate two weeks ago, which voters expected Obama to win by a 51%-29% margin.

Also worth noting, Biden vs. Ryan was judged a tie. "As many say Biden did the better job (47%) as say Ryan (46%)."