Environmental advocates on Capitol Hill are lashing out at the Koch Brothers' influence on American politics, accusing the conservative duo of being polluters and calling for limits on their power.
Rep. John Sarbanes, D-Md., explains, "The congress has been dominated and influenced too much by big money that comes in from polluters across the country."
"We have to get money out of politics and we have to put voters back in," says Michael Brune, executive director of Sierra Club. 
The Sierra Club and other groups are looking to counteract Americans for Prosperity, a conservative group back by David and Charles Koch. 
Dave Levinthal, Senior Political Reporter at the Center for Public Integrity, emphasizes that if someone has the resources, they can donate to whoever and whatever they'd like.
"If you've got a lot of money, if you've got cash behind you," explains Levinthal, "you can spend it on causes that you care about, or for that matter, candidates that you care about."