This is a tough one for me. Probably Romney, although I must admit that Big Bird is one of my favorite Sesame Street characters. Why not having them run on a ticket?
"Hey Big Bird! Would you like to be my running mate? After all, you gotta find a new job since I'm going to fire you!"
At least all Romney wants to do is fire Big Bird. Ryan would probably shoot him and serve him up for Thanksgiving.
PBS has such a huge budget already from contributions and other non-government sources that cutting funding wouldn't hurt them significantly, and almost certainly would not jeopardize Sesame Street. So rest easy, Big Bird is not going anywhere.