[Norman Bates]

I don't understand why the President backed Specter in his campaign over the more conservative Republican.

[mysonsfuture]

At the time, Bush felt the senate races might be close, and felt he needed Penn.

[Sola Veritas]

"I don't understand why the President backed Specter in his campaign over the more conservative Republican."

Politics is often a game of expediency and compromise. I doubt Bush wanted Specter to remain in office. However, in PA the conservative running in the primary would probably not be able to win a general election. Specter only won in PA because he is a RINO. Remember, Bush did not win that state.

The president and his advisors probably thought, "better a RINO in the senate than a Democrat." I don't like it myself, but that is pragmatism at work.