It won't happen, but if I were a funnyguy SNL writer I'd do a repeat of the "I can't believe I'm losing to this guy" skit, though this time with Romney saying it. This time the joke wouldn't be about GHWB being a bit of a buffoon, it would be about Romney's sense of entitlement with respect to the Kenyan Muslim Socialist in the White House.
But I doubt they'd go there.