MSNBC's Chris Matthews went after socialist Sen. Bernie Sanders (I., Vt.) for how he intended to pass his left-wing, populist proposals in Washington during an at-times contentious interview Thursday night.

Sanders, who called himself an "outside-the-Beltway guy" in spite of being in Congress since 1990, repeatedly clashed with Matthews. The MSNBC host sounded like the Democratic candidate who's sought to portray herself as a pragmatist, Hillary Clinton.

The interview, held live at the University of Chicago, was part of the Hardball College Tour.

While trumpeting his call for tuition-free public colleges and addressing high student debt, Sanders said he knew the next question would be how he would pay for it.

"I haven't asked that. I've asked you how do you pass that through the Senate," Matthews said. "How do you get 60 votes for any of this?"

"We're going to pay for it through a tax on Wall Street speculation–" Sanders said.

"Who's going to pass that tax?" Matthews asked. "The Senate's going to pass that?"

"Chris, you and I look at the world differently," Sanders said. "You look at it inside the Beltway. I'm not an inside-the-Beltway guy. I am an outside-the-Beltway guy."

"But the people that vote on the taxes are inside the Beltway," Matthews said.

"And those people are going to vote the right way when millions of people demand that they vote the right way," Sanders said, touting his ability to rally young people and their parents to emulate European countries in this regard.

Matthews asked if Sanders could name one senator who would back any of his proposals, such as Chuck Schumer (D., N.Y.).

"What you're not catching on, I have to say this respectfully, you're a nice guy," Sanders said. "You're missing the point, alright? If you look at politics today as a zero-sum total … you're right."

How will that change, Matthews asked, after Sanders listed off statistics like low voter turnout and the influence of big money in politics.

"We're going around in circles," Sanders said, as the two repeatedly talked over one another. He went back to his campaign message of starting a political revolution that would build the culture necessary to enact his socialist ideas.

"The difference that you and I have is you're looking at politics in the way that it is today," Sanders said. "What I am trying to do is not just pass legislation. I'm trying to change the face of American politics, getting working people to stand up and fight for their rights."

Matthews, still sounding the pragmatic tone, suggested the people who could propel Sanders into the presidency wouldn't be patient if he couldn't make good on his promises quickly.=