There is much speculation about Romney's VP choice. I heard earlier today that it might be a "shocker" with someone mentioning Guilianni?

For some reason I just don't see it being a woman and I am uncertain if he'd pick either Jindhal or Rubio, tho it might help him with minorities. I've heard most pundits say it'll be more middle of the road (?), like Portman or Pawlenty (both being just as boring as Mittens.)
Yet, in the long run, and for the most part, do people really vote for a candidate by whom his VP choice is? Not to say VP doesn't matter, but I think most people vote for the main candidate. (Palin was/is an exception I guess, IF indeed people voted for McCain just because of Palin)
TIS