I'm also thinking it could be Sarah.
Romney brings in the RINOs, Sarah brings in the real conservatives. It's a cruel-world, realpolitick solution, but it would work. And after all, look who's running for re-election.
Aw hell, I thought she was running for president, too. So like everyone else, I'll just wait and see what happens.
Why would she be willing to take second chair 2 elections in a row? Palin is OUT for the foreseeable future...