When you start seeing headlines like this...

"Santorum-Gingrich Ticket Floated By Gingrich Adviser"

...you know someone's campaign is in real trouble. I can't really picture Santorum welcoming Gingrich onto a ticket with him, in part because I think these last three Republican candidates genuinely loathe one another on a deeply human level. And I don't think the motivation is there: Santorum would pick up the not-Romney vote regardless of who he picked or didn't pick as a running mate. But Democrats should be hoping that this is a sign that maybe Gingrich is ready to fold up his enormous ego and go home—a strengthened Santorum wouldn't be able to pick up the delegates to win the nomination, but he would be able to pick up just enough delegates to keep this thing going to the very last primary, and possibly the convention.