Sen. Bernie Sanders (I-Vt.) departs a news conference after announcing his candidacy for the 2016 Democratic presidential nomination in Washington on April 30, 2015. (Jonathan Ernst/Reuters)

Sen. Bernie Sanders (I-Vt.) on Sunday reiterated his pledge not to accept super PAC support but stopped short of knocking Democratic front-runner Hillary Clinton’s decision to court allied super PAC donors.

“I understand where she is coming from. [But] I will not have a super PAC,” Sanders, who last month launched a bid for the Democratic presidential nomination, said on “Face the Nation” on Sunday. “...I don't think we're going to outspend Hillary Clinton or Jeb Bush or anybody else, but I think we are going to raise the kinds of money that we need to run a strong and winning campaign.”

Although Sanders did not criticize Clinton about her tacit support for an allied super PAC, about which The Washington Post’s Matea Gold reported last week, he nonetheless stressed — without naming names — his belief that the American political system gives outsize influence to millionaires and billionaires. He said a central consideration for Supreme Court nominees should be their position on the Citizens United decision.

[Hillary Clinton cements her support for allied super PAC.]

“Let me say it this way: If elected president, I will have a litmus test in terms of my nominee to be a Supreme Court justice, and that nominee will say that we are going to overturn this disastrous Supreme Court decision on Citizens United,” he said. “Because that decision is undermining American democracy. I do not believe that billionaires should be able to buy politicians.”

Asked about the differences between Clinton and him, Sanders — who described himself as "the most progressive member of the United States Senate" — said he has voiced strong opposition to the Trans-Pacific Partnership and the Keystone pipeline while Clinton's positions remain unclear. He also knocked Clinton on her oft-criticized 2002 vote to authorize the use of military force in Iraq.

“In terms of foreign policy, Hillary Clinton voted for the war in Iraq. Not only did I vote against it, I helped lead the effort against what I knew would be a disaster. In terms of climate change, I have helped lead the effort against the Keystone pipeline. I'm not quite sure if Hillary Clinton has come out with a position on that. So those are just some of the areas where we differ.”

Sanders suggested that the “massive dissatisfaction in this country today with the corporate establishment” could give him an edge in the Democratic primary.

"[L]et me say that I have known Hillary Clinton for 25 years.  I respect her and I admire her.  But I think we're living in a very strange moment in American history," he said.

Sen. Bernie Sanders (I-Vt.), a White House contender in 2016, is known for his stances on budget issues and war. Here are his takes on Obamacare, Social Security and more. (Julie Percha/The Washington Post)