I have had this thought for some time now, but in light of recent events I am ready to go on the record: I predict that John McCain's running mate on the GOP ticket will be none other than his former rival Mitt Romney. Romney would provide a balance to McCain in many ways, balancing the ticket with his relative youth, his smooth-talking GQ looks and charm, his economic and business experience, and his conservative "cred." In addition, he already has national name recognition as well as the experience of being poked, prodded and investigated by the national media. It's doubtful there would be any October surprises as a result of his being put on the ticket. And his acceptance of the job would make a huge statement about the ability of the Republican party to come together in the general election.
I could be completely off the mark here. But for what it's worth, that's my prediction. Check back in a few months to see if I was right!