To no one's surprise, I will have to disagree with Rich and others who have said that Russert was easier on liberals than he was on conservatives.
I know when Howard Dean appeared on MTP during the height of his frontrunner status, I hated Tim Russert with a passion. Conversely, later on, I came to see the failing was really Dean's fault. He didn't prepare. Russert called him on a lot of stuff that Dean had not really wanted to talk about and he got tripped up.
Many times, I felt that Russert had acted as a tool of the right. He was deeply involved in the Plame Affair but considering how folks have talked about him since he died, I think that he was used by Matalin and BushCo. He probably trusted people too much and got burned because of it.
And I know many times I've just been pissed because he'd have the panel stacked with rightwingers like Matalin, Broder and Saffire.
So, I think this is one of those situations that since everyone seems to think he was against them, then he must have been trying to be objective.