The race for the White House come at a price, and a significant one at that. It's difficult to stomach, but this year it's estimated that each candidate raised just under a billion dollars for their respective presidential campaigns. With Romney outspending Obama by nearly $60 million, it's interesting to see where all this money is actually coming from. Continue below to see how the 2012 U.S. presidential campaign became the costliest political race in world history.