I understand your rationale, but I am convinced that Santorum is Obama’s “low hanging fruit”.
The guy has the charisma of an unseasoned bowl of grits and would fail miserably in the general election. I think that despite his obvious appeal to the social conservatives, there are just not enough of them to elect a President, especially when the support of fiscal conservatives and independents will be unenthusiastic.
Santorum is Obama’s dream opponent and I don’t think that is what we want to give him.