Perry is generally regarded as a lightweight within the Republican party. He was re-elected in 2006 with only 39% of the vote, so I don't think his political base in Texas would be all that helpful to the GOP ticket. Plus Perry was never a firm backer of McCain, in fact, I think he claimed the other day that he was his 3rd choice to be President. I think McCain would want someone a bit more loyal. Texas is going Republican his year anyways, so he won't bring much to the ticket.
