Liberal intolerance

Are mainstream liberals prejudiced towards conservatives?

This guy and this guy think so.

UPDATE: This guy has had similar experiences:

I'm a very unusual animal where I come from, sort of like a large reptile or rodent. Just a mild-mannered profession of non-Democratness is very disturbing to the equilibrium. For some reason, it's OK to wax polemic for a half-hour at a time if you are dissing Bush, but non-Democrats must stay in the closet.