WASHINGTON (CN) - Sen. Bernie Sanders rallied Democrats in a live town hall broadcast by CNN Monday night, offering a gut check on the fight ahead for the Democratic Party.
CNN correspondent Chris Cuomo moderated the program, leaving the 75-year-old Vermont senator to do what he arguably does best: bring attention to large scale issues facing voters.
The town hall was held at George Washington University, and Sanders fielded questions on climate change, trade policy, the economy, health care, and education. Throughout, the senator refused to mince words about the opposition Democrats face as both the House and Senate have swung to a full Republican majority.
"What the GOP did, literally did on the day [President] Barack Obama was inaugurated was decide on a strategy of obstruct, obstruct, obstruct," he said. "They said let's do everything we can to make sure he accomplishes as little as possible."
Despite holding this opinion, Sanders said it would be a mistake for the Democrats to pursue an obstructionist course over the next four years.
"Where Trump has ideas that make sense and we can work with him, we should," he said. "But he ran a campaign based on bigotry, sexism and xenophobia and on [those] issues, I personally will not compromise."
After Sanders lobbed a few more barbs at Trump, Cuomo pressed him for his take on a plea made by Trump adviser Kellyanne Conway Monday morning. Conway appeared on Cuomo's morning show, defending the President-elect's mocking of a disabled reporter while he was stumping last year.
Conway asked the public to consider what is in the billionaire businessman's heart and not so much what he says.
"You're not a heart surgeon," Sanders said amid peals of laughter. "You can't know what is in someone's heart. Generally speaking, when somebody says something, they mean it and we have a right to accept that at face value."
And then the gloves came off.
"This will sound rude and partisan and I'm not the only person to say this, there are Republicans who say this, but we are dealing with a pathological liar," Sanders said. "There are many conservatives that aren't liars, they have their point of view, but time after time [Trump] says things that are blatantly untrue."
Cuomo asked if he was comfortable with the description being aired on national television.
"That's a reality," Sanders retorted.
The Sanders town hall came as the Republican-led Congress was preparing for confirmation hearings on the president-elect's cabinet nominees.
The hearings for Trump's hotly debated pick for attorney general, Sen. Jeff Sessions, and his selection for head of Homeland Security, retired Marine Corps Gen. John Kelly, kick off Tuesday.
Sessions, who once lost a federal judgeship on allegations of racism, has been perhaps Trump's most divisive nominee. After town hall attendee DeMarquin Johnson asked if the senator would support Sessions' confirmation, Cuomo pressed Sanders to show his hand.
Sanders said he would listen carefully to what Sessions has to say during the hearing, but that he shared Johnson's concerns. Flat out rejection might be reserved for Trump's pick for EPA head, Scott Pruitt, he said.
David Bright, a farmer from Maine, told the senator that for those whose "job it is to feed the country" there is "no room for climate change denial."
Citing people's experience with droughts, floods, rising sea levels and the bulk of scientists who accept climate change as a reality, Sanders said he will listen to what Pruitt has to say during confirmation hearings, but allowed that he could not "imagine voting for somebody who does not believe that climate change is real."
Cuomo asked him to explain why he was able to take a hard line with Pruitt, but seemed less inclined to do so with Sessions.
"All I'm trying to do here is be polite. If I said I'm going to vote against these guys, the next question would be, how can you vote against them? Before I vote against them, I want to hear what they have to say," Sanders said.
Sanders also offered reassurances about the Democrats fight to preserve the Affordable Care Act, which the GOP has sworn to repeal. Speaking to a 30-year-old woman with terminal breast cancer who said she relies on ACA for coverage of her pre-existing condition, the senator said he spoke on behalf of nearly every member in the Democratic caucus.
"I'm going to do everything I can ... but we damn well aren't going to see it repealed and have no replacement at all," he said.
Cuomo again pushed Sanders to open up about trust for the incoming president, asking him if he thought Trump would keep his word on pre-existing condition coverage.
"The problem is, he says that he will. But other republicans are not so sure. The complete repeal would not do only do away with pre-existing conditions, throw 20 million people off Medicaid, raise prescription drug prices for seniors, do away with Medicare and privatize it, but it would also give huge tax breaks to the wealthiest people in this country," he said. "There's a limit on what you can do to preserve the 'good parts.'"
Sanders encouraged listeners to "keep the faith," saying that focusing on who is president should be far less important than what is actually done and that's where the Democratic party can make headway.
"You cannot be on the side of Wall Street, drug companies and insurance companies and then go to working people and say, 'Hey, I'm on your side,'" he said. "They're smart enough that they're not going to believe you."
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