Well, it's not that Beck is unpopular; it's that he's very popular with people of a particular political ideology.

In fairness, though, he is sort of the canonical example for "I'm just asking questions, here!". (And I wasn't one of those voting you down on this.)

I think referring to the phenomenon itself is enough to make one's point on the issue, and it's not necessary to identify a person who does it a lot.