One of the things we’re already hearing a lot about, and will continue to hear about until the GOP convention, is the debate - or rather, guessing - over who Romney will pick as his Vice Presidential nominee.
Every four years, various members of the media ask the same old questions, one of which is whether or not certain VP candidates will help the nominee to win particular states, specifically the home state of the VP nominee.
In May 1989, Robert Dudley and Ronald Rapoport revealed some interesting statistics about the perceived importance of regional importance in selecting a Vice Presidential candidate - they noted that between 1952 and 1980, only 1 ticket did not show regional balance and between 1884 and 1984 only 5 out of 52 tickets were not regionally balanced (American Journal of Political Science, Vol. 33, No. 2, pp. 537-540). Their study showed that in these elections the VP nominee only made a difference in 3 elections (1892, 1968 & 1980), and thus was not a significant factor in voter choice. Lee Sigelman and Paul Wahlbeck came to a similar conclusion in 1997 (American Political Science Review, Vol. 91, No. 4, pp. 855-864).
Recent polls would seem to confirm these studies. A poll by PPP showed that Romney received no bounce in Florida with Rubio hypothetically on the ticket (of course, PPP is a Democratic polling firm, and there have been accusations about bias in the past, but they have been fairly accurate during this primary cycle). Similarly, recent polling by Quinnipiac University shows that Ohio Senator Rob Portman would offer no help to Romney in this crucial swing state (Sources: CNN, Wall Street Journal).