The search for Romney's running mate

With Mitt Romney locked in as the Republican presidential nominee, the one major unknown as the general election campaign picks up is who Romney will choose as his running mate. His campaign has officially begun its search, and Romney has taken some contenders with him on the campaign trail. Political observers hang on every comment made by Romney and the prospective candidates, looking for hints and tells. But barring a wild card selection, these are the most likely choices to join the Romney ticket.