Nate Silver’s dour forecast about the Democrats’ diminishing likelihood of holding on to the Senate isn’t the only cause of liberal angst. The dreaded Koch brothers—that’d be David and Charles Koch, the fifth- and sixth-richest men on the planet, according to the Bloomberg Billionaires Index, who are together worth precisely $100 billion—have been plowing money into the conservative group Americans for Prosperity, which has unleashed a fusillade of negative ads against vulnerable Democratic senators. In fact, AFP has dramatically outspent the Senate Majority PAC and the House Majority PAC, the main outside Democratic groups.
This chart from Kantar Media CMAG, created for the Cook Political Report, illustrates just how badly Democrats are being outspent:
