Santorum is the Republican Conference Chairman, #3 in the senate pecking order. In that role, Santorum is also the Senate's mouthpiece. Santorum also endorsed Specter over Toomey, which he did not have to do. I believe he made comments vouching for Specter's ability to perform as Judiciary chairman.
Conservatives are not there to agree with you on every issue.
No one appointed you king or god.
"My way or the Highway" thinking is stupid.