I think you need someone closely allied with Bush. Bush is hugely popular in Texas, obviously, and like I said, Bush took the district easily (56% of I remember correctly), but Edwards didn't have a problem staying in.
But when you have someone who is obviously tied very closely to Bush, I think people would vote for a Bush over Edwards.
Wait, didn't we just do that in November in the P/VP election? :)-
George P. is going to wait a little while and then run for Governor. Probably in Texas, but maybe Florida. I don't think he's even thinking of running yet in the short run.