Hours after suspending his campaign for president, Vermont senator Bernie Sanders wasn't yet ready to endorse the presumptive Democratic nominee, former vice president Joe Biden—no matter how many different ways Late Show host Stephen Colbert broached the question.

“It's no great secret that Joe Biden's politics are different than mine. But I have known Joe since I came to the Senate in 2006, worked with him when he was vice president in the Obama administration. And what I would say to people is that Joe is a very decent human being—I know his wife, Jill, as well as a wonderful person—and I hope to be able to work with Joe to move him in a more progressive direction,” Sanders said to Colbert on Wednesday night in his first interview since dropping out. (Sanders will, however, remain on the ballot in an effort to collect delegates, with the hope of exerting “significant influence on the party platform” at the Democratic National Convention, he said Wednesday).

“I think Joe is a good politician and he understands that in order to defeat the president, in order to defeat [President Donald] Trump, he's going to have bring new people into his political world, and he's going to have to listen to their needs—young people, working people—and maybe start moving in a different direction to some degree than he has in the past,” Sanders told Colbert. Pressed by the host to label his comments as a “full-throated endorsement” of Biden, Sanders side-stepped the question.

“We’re going to be talking to Joe, and we are, and we're talking to his team of advisers,” he said as Colbert smiled at Sanders' parry. “But what I have said—I can tell you this, Stephen: what I said from the first day when I announced my intention to run for president, I will do everything that I can to make sure that Donald Trump is not reelected. I believe Trump has been the most dangerous president in modern history in this country, and we're seeing his narcissism, his ignorance playing out in terms of the pandemic we're experiencing right now. But I will say that we are talking to Joe, and we're talking to his team about how we can work together.”

Not one to let someone off the hook, Colbert added, “So you'll have those conversations, and then decide just how full your throat will be when you endorse him?”

Sanders laughed. “Right. That's what we're working on right now, how we can best go forward together,” he said.

But Colbert didn't stop there. He also asked Sanders what it would take to get Sanders' supporters into Biden's camp, pointing out how contentious the 2016 presidential campaign between Sanders and Hillary Clinton had been. “Because there's still hard feelings from some of Hillary's people, the feeling that your endorsement was not full-throated enough in 2016. What can Joe do to win over [your] people?” Colbert said.

Sanders, however, showed little interest in relitigating the past. “In terms of 2016, I worked as hard as I could to see that Trump was not elected,” he said, before providing a list of ways Biden could move into a more progressive direction. “It's no secret. The facts are pretty clear that during this campaign, we did very, very well with younger people—by that I mean not just people 20 years of age, but 50 years of age or younger. Joe did very, very well with older people. I think what Joe has to do, and I think he will do, is look at what are those issues that young people and working-class people who supported me, what are they concerned about.” Sanders cited wages, climate change, and tuition-free public colleges and universities as key agenda items.

How Sanders drives his supporters going forward will be a major storyline in the forthcoming election. (Trump is already sowing discord, tweeting Wednesday that aggrieved Sanders voters should come to the Republican party.) That fact wasn't lost on Colbert. During his monologue before the Sanders interview, he joked, “Bernie Sanders is saying Bernie Sanders can’t win? Man, he is going to catch hell from Bernie Sanders supporters.”

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