Guiliani, Pataki, Bill Owens are some good choices. I've also always liked Mark Racicot (sp?).
Guiliani is the best choice. Who knows, Cheney may retire due to health reasons in the next term and Guiliani named as VP. Nice thing is he wouldn't have to pardon anyone. I also agree that the Pro Abortion stance would be mitigated by congress. It would take a little fight out of the beast, too.
Condi would be fantastic but her inexperience would hurt her. Remember, the beast has been President before.
Mark Racicot - Hmmmm, could he overcome the environment knock? Probably with conservatives but.....storng choice otherwise, he was on Bush's re-election committeeand was RNC chairman for a bit.