By Dana Bash
Washington (CNN) -- Flooding the airwaves this election year in battleground states across the country are Democratic ads featuring two men not on any ballot, and not even politicians.
They're the Koch brothers, billionaire businessmen and GOP mega donors.
Senate Majority Leader Harry Reid takes the unusual step of regularly ripping Charles and David Koch from the Senate floor. He says they have "no conscience," calling them "un-American." And now, is proposing a constitutional amendment to ban the kind of anonymous political giving the Kochs engage in and, some experts say, perfected.