Santorum has lost a huge amount of credibility in my book. to see him make all those impassioned, eloquent, brave arguments for life on the floor of the Senate, and then support a man like Specter, who has no respect for life whatsoever, was repulsive. His support for Specter in light of his most recent comments is just pathetic.
Another thought is that maybe the pubbies want it to be Spector who reads the political writing on the wall and decides to resign the Chairmanship, rather than push him out. They need to get Spector on the reservation and keep him there because they need his vote.