Marco Rubio, 40, would be seen as a bridge to the growing Hispanic population that votes heavily in favor of Democrats. At the same time, picking him could energize conservatives who have been less than enthusiastic about the more moderate Romney. Counting against Rubio would be his relative youth and inexperience. He has only been a senator since his 2010 election and has no major legislative track record. Many see him as a contender for the 2016 Republican presidential nomination, which could be a big reason why he might want to sit out 2012.
The likely front-runners and long shots on Romney's short list.