Rubio may not be the right choice, but I think an ultra-conservative is the best bet if you want to give Mitt Mormon the best chance to win. As I said previosuly, he's far enough left that he's going to attract disillusioned independents no matter who his running mate is.
I happen to think Rubio would be a good choice. Maybe not the best one, but while he's well regarded by the Tea Party, he is not seen in the same "wild eyed crazy" way as some other Tea Party leaders (except by the far far left of course, who don't really count anyway). He's Latino, which helps. There are a lot of Latino voters who lean to the right, but tend to be afraid of certain issues (immigration specifically) if anyone but a Latino conservative is talking about them. His stance on immigration does not hurt him with mainstream Latino voters at all.
The bigger issue IMO, and one which Rubio may or may not address is the south. And before anyone starts throwing knowing looks and saying "southern strategy", the reality is that the primaries have shown that Romney is weak in the south (duh). His VP pick pretty much absolutely has to be someone who can get voters in southern states to vote GOP. There's a fair number of possibilities to be honest.
It will not be Santorum. Too much baggage. It probably wont be Gingrich. He's too similar to Romney in the eyes of voters (although he is stronger in the south). It has to be someone who will be viewed positively by religious right conservatives, but not be scary to moderates and independents. That's going to be tricky IMO, but doable. He might go for a woman, but the pickings are slim. Not because there aren't plenty of conservative women who could do the job, but because the left tends to single them out for special attention and assault (can't allow women to choose to be anything but liberal you know!) so most of them have been so demonized (or are afraid of being Palinized), that any choice can end out being dangerous.
Rubio (or Jindal) also make sensebecause they are younger than most of the VP candidates being kicked around, and if they want to give Mitt the best chance to win, they have to take some of the younger voters away from Obama.
Yeah. I agree to that as well. Although it doesn't necessarily have to be about hip appeal. They got that with Obama and young voters are largely unhappy with the result. I think that this time around, they just need to get the message that fun and games and clever idealistic slogans are great, but if you're young and want to have a good job when you get out of school, voting Republican will be a better choice. Obama's already provided enough failed promises and hopes and dreams to fill the negative side of that equation. Just need to present an alternative and appeal to young voters taking responsibility for building a better tomorrow, not just voting for hope and seeing it dashed.