Don't let anyone tell you different, the Senate is not a zero-sum institution. Just because you control +%50 of the Senate does not mean you manage it as if you own it. The Congress is meant to be a place where policy can be discussed and the states and the people can have a voice in how the government goes about its business. Under the Republicans it has become a place to punish those who disagree with them. Sen. Arlen Specter (R-Penn) found this after he publicly voiced opposition to strong anti-Roe judicial nominees. Sen. Specter has been no friend to liberals, but has been consistently pro-choice. He has since been in full apology mode in order to try and maintain the possibility of Chairman.
From AP/CNN via Josh Marshall:
Sen. Arlen Specter must prove to his Republican colleagues that he is the right man to head the Senate Judiciary Committee in the next Congress, Senate Majority Leader Bill Frist said Sunday.
Frist, R-Tennessee, would not say if he backed Specter, R-Pennsylvania, for the job. Specter will make his case to GOP colleagues this week when Congress returns for a postelection session.
This is what the Republicans do to their own.