Here's Stanley Fish:
Commentators who explain smugly that O’Donnell’s position on masturbation (that it is a selfish, solitary act) is contradicted by her Ayn Rand-like attack on collectivism, or who wax self-righteous about Paladino’s comparing Sheldon Silver to Hitler and promising to wield a baseball bat in Albany, or who laugh at Sharron Angle for being in favor of Scientology (she denies it) and against fluoridation and the Department of Education, are doing these candidates a huge favor. They are saying, in effect, these people are stupid, they’re jokes; and the implication (sometimes explicitly stated) is that anyone who takes them the least bit seriously doesn’t get the joke and is stupid, too.
Sometimes I think of the political blogosphere as a huge commons. An individual blogger can gain in readership or influence by attacking or ridiculing some enemy, but at the cost of making that enemy stronger in the world as a whole.
I also believe that every time the words "stimulus" or "fiscal policy" are blogged it helps the electoral prospects of the Republican Party, no matter what the content of the blog post.