I wouldn't bet on it. Given McCain's age, he will want to pick someone considerably younger than himself as VP. That would eliminate Lieberman.
I think Gov. Pawlenty is much more likely. We need someone who will help us pick up a blue state with a lot of EV.
I appreciate your concerns, but McCain isn't interested in what we conservatives need. His entire career is based on sticking it to us every chance he gets. He's been my Senator for decades; this is how he operates.
Just look at all his major bills: McCain-Lieberman, McCain-Kennedy, McCain-Feingold, etc., etc. If he gets the nomination, he will no longer about "what's best for the GOP." He will tack WAY to the left and form a "unity ticket."