When Vermont Senator Bernie Sanders (I) sat down with Bill Maher yesterday, you might've expected the interview to be filled with barbed remarks for President Donald Trump. But Senator Sanders actually came out swinging against the party that he ran for in 2016.

"It is simply not good enough to attack Trump every single day," he told Maher, referring to his Democratic colleagues' tendency to slam the president without offering alternatives to the Trump administration's policies. "What we need to do is bring forth an agenda that working people all over this country are going to respond to."

Without an agenda that resonates with the working class, Democrats are doomed to loose the midterm elections, according to Sanders.

"Let me be very clear," he added. "In 2016, it's not that Trump won, it's that Democrats lost. And for too long, the Democratic Party has been dominated by wealthy campaign contributors. They've got to open the door to people who work with their hands. People who take showers at the end of the day, not the beginning of the day."

And if they do that, Sanders thinks the Democrats can retake both the House and the Senate this Fall.

"Four years ago in 2014, we had the lowest voter turnout for a midterm election since World War II - 37 percent of the people voted. If we increase that turnout by 50 percent, Democrats win the House, win the Senate. And that's what we have to do."

Check out the full interview in the clip below.