I just thought of this last night. What about...... John McCain?
I was shot down for suggesting this a while back. But I actually think it would be an inspired choice that I could get behind. The man may not be the most conservative guy in the world, but he's got some "down home" appeal that makes him a lot more relatable to voters than Romney or Obama.
It'll never happen though.
That'd be a terrible pick. He really doesn't bring much to the table other than a "down home" appeal, and factoring in his 2008 campaign, he really wouldn't add much to Romney's numbers.