There are still more than five months to go until the GOP formally nominates a candidate at the Republican National Convention. Although Mitt Romney has the lead in delegates, the contest is far from over.
But not having a nominee hasn't stopped speculation from running wild about which name will end up on the bottom half of the ticket. Some of the most-mentioned candidates include early state governors, popular swing-state politicians and pretty much anyone who's ever been described as a "rising star" of the Republican Party.
Here's a look at some potential picks: