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Story highlights

Bernie Sanders says he wants Supreme Court nominees who'd overturn the Citizens United decision

Sanders took several shots at the Koch brothers during an event in Chicago on Monday

(CNN) —  

Bernie Sanders said Monday that a commitment to getting big money out of politics would be his litmus test for Supreme Court nominees.

The Vermont senator and Democratic presidential contender told students at a University of Chicago Institute of Politics event that he wants to ban billionaires like conservative business moguls Charles and David Koch from influencing the outcome of elections.

“No nominee of mine to the United States Supreme Court will get that job unless he or she is loud and clear that one of their first orders of business will be to overturn Citizens United,” Sanders said.

He was complaining about the 2010 ruling that lifted restrictions on outside groups’ spending on elections. Sanders has called for public financing of campaigns – which means candidates would get tax dollars to spend on their efforts but wouldn’t be allowed to raise and spend money otherwise.

He also took several specific shots at the Koch brothers.

He complained about their fundraising network’s plans to spend more than $900 million in the 2016 election cycle to bolster conservative candidates.

And he said candidates’ donors and super PACs have more influence on their campaigns than the candidates themselves.

Super PAC fundraising reports: 5 top takeaways

“You are not looking at democracy, you are looking at oligarchy – and we have got to change that,” Sanders told the students in Chicago.

“I do not exaggerate when I tell you that the foundations of American democracy are being undermined,” he said. “American democracy is not supposed to be about billionaires buying elections.”