William Kristol: "Russ Feingold, now freed of his Senate responsibilities, is liberated to consider a Gene McCarthy-like run against the president in the 2012 primaries on an end-the-war platform -- pre-empting Howard Dean, who is undoubtedly also considering such an effort."
Interestingly, Ben Smith notes that at the conclusion of Feingold's concession speech, he says, "It's on to our next adventure. It's on to 2012! Forward!"