Good point, Wesley.

The oldest source I could find was the one I linked to, from Slate. Slate is not known for publishing hoaxes.

I'm inclined to think it's real. You'd think if someone were trying to smear Santorum, they would go the whole hog and put "Rick Santorum" on it, instead of "S. C. Team Santorum." As it is, the card has easy deniability.

And it's hard to check, because I understand the South Carolina office has been shut down. The SC Primary happened January 21. Who knows where their records would be now?

If you think only the "mainstream media" has credibility, then we're still waiting. Politicker isn't any more mainstream than Slate.