It's the Koch Brothers! They rank 4th in the newest Forbes 400 list of the wealthiest Americans, up from 5th last year. In fact, the fortune of Charles and David shot up 14% just from March to September 2011.
What's most interesting - despite the Koch brothers' war on President Obama and crazily overheated rhetoric against him, the Koch brothers' fortune has grown wildly during President Obama's first term. It's up 79%, from $14 each billion in March 2009 to $25 billion each in September 2011.
Wait ... you don't think the Kochs' opposition to Obama is about an extremist political crusade and not sound economic policy, do you? Nahhh.