Who will be Romney's running mate?

i'd go with natalie portman

she's a cutie

She definitely has more name recognition than the Senator lol. (She's probably a Democrat, though).

serious question, is there anything legally that says he can't ask a democrat to be his running mate?

to me that would be the perfect match

No, not legally.

An aside, I think it's pretty funny that Condi Rice is the frontrunner for Republicans. Many seem to think she voted for Obama in the last election, so if chosen, it would be a hoot to see her response to that question.