President Barack Obama’s re-election campaign continues to press the point that Mitt Romney made a lot of money in ways that most people don’t. On July 17, 2012, the campaign unveiled an ad in Pennsylvania, a swing state where Romney was making an appearance. The ad begins with a narrator saying, "Tax havens, offshore accounts, and carried interest. Mitt Romney has used every trick in the book." The last item in the list -- carried interest, which refers to a type of income typically earned by managers of hedge funds and private-equity ...