Santorum had some flashes of conservative cred. I was on his side during the Terri Schiavo debacle, as he stood for her on his deep convictions and principles. But Pennsylvanians disagreed, and I think he paid for his position with his career, and she ended up murdered anyway. At least he doesn't have her death on his conscience.
As a politician, principled, you're damned. Unprincipled, you're damned.