Bernie Sanders tries on a new role in 2020: Inside player

Then, just as surely, Sanders would pull up short.

"Joe is a friend of mine," he would offer as a caveat, "and a decent guy," before going on to lament Biden's voting record or prospects in the general election.

Nearly two months after the primary effectively ended, Biden's campaign and Sanders' senior leadership have successfully crafted a ceasefire in the ideological warfare that has dominated the Democratic Party, and its emboldened left wing, for the past five years. Deep and abiding divisions on major issues make the peace a tenuous one, but the personal bond between Sanders and Biden, set against the party's evolving power dynamics and a country veering from crisis to crisis under President Donald Trump, has set the stage for Democrats to enter the general election this fall with a unity of purpose they lacked in 2016.

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The détente is being quietly shepherded by Sanders campaign manager Faiz Shakir and top Biden aides Anita Dunn and Ron Klain. Shakir and Dunn, who ruffled Bernieworld when she compared Sanders' performance to that of a "protester" after his and Biden's final debate, speak regularly. And in an interview last week, Shakir praised her for setting a "tone and tenor" in private conversations that encouraged the relationship.

"They're operating with the best of intent. Now that doesn't necessarily mean you're going to get all the outcomes that you want," Shakir said. "Obviously we have to see where the outputs are in terms of these task forces (created by the campaigns), but we're operating with full reality, understanding that we're not going to get everything we want."

'It's been encouraging'

In May, the campaigns announced the creation of six policy-focused "unity" task forces and charged them with hashing out recommendations for Biden and the party to consider and potentially add to the platform. The meetings began this month, remotely via tools like Zoom, and the groups are expected to present their work to Biden by the end of June, Shakir said.

Participants have been mostly tight-lipped about the details of the conversations, but Varshini Prakash, the executive director of the Sunrise Movement and member of the climate task force co-chaired by New York Rep. Alexandria Ocasio-Cortez, tweeted out a video last week describing herself as "cautiously optimistic" after two meetings.

"I've also seen the Biden folks bringing a lot," Prakash said, after praising Ocasio-Cortez and environmental justice activist Catherine Flowers. "Rep. (Donald) McEachin from Virginia has been bringing a ton of ideas for how to do bottom-up policy making where we listen first and craft policy out of what communities need. (Former EPA administrator) Gina McCarthy has been stressing the importance of timelines and urgency -- that the benefits of this transition need to get to people today and by tomorrow, not by 2050. So, it's been encouraging."

That progressive leaders, some more accustomed to occupying lawmakers' offices than sitting across from them at a virtual conference table, have chosen private negotiations over public spats is both a marker of the movement's success and a testament to Biden's unique political talent.

A number of Sanders aides were quick to note, as they have in the past, that Biden was one of the few Democratic establishment figures to connect with Sanders back when the democratic socialist from Vermont was still perceived as a Capitol Hill curiosity, an eccentric on the margins of the mainstream.

"Very few people in the Senate went out of their way to say, 'Hey Bernie, how you doing?' I'm not saying they went out for beers every Friday, but Biden made an effort to build a relationship of Bernie, to reach out to him, that made an impact on Bernie," said Sanders campaign pollster Ben Tulchin.

Tulchin described himself as a "leading advocate" during the primary for Sanders to more aggressively "make the contrast" with Biden on the trail and in debates.

"Bernie consistently was reluctant to do it," he said. "In part because he had a rapport with Biden. He would do it, but he never liked doing it. He didn't want to do it."

Another former aide to Sanders, who worked closely with him on both campaigns, remembered that the relationship extended beyond the Senate, where they only briefly overlapped, through Biden's years in the White House. That included conversations during the 2016 primary, when the two would occasionally talk on the phone at a time when most establishment figures were steering clear.

But other Sanders allies believe the stories of the pair's personal affinity are either overblown or overestimated in the current context. What's changed, they argue, is simple: Sanders has a robust political base and his signature policies, like "Medicare for All," are popular.

"I think a lot of people might turn to talking about who these two people are, what kind of relationship they have, all that kind of stuff. I think none of that matters," said Sara Nelson, the international president of the Association of Flight Attendants. "That's all sort of nuance, sure, but it doesn't really matter. The significant difference here is that Bernie Sanders has way more power in 2020 than he had in 2016."

From 2016 to 2020

Going back to 2015, during Sanders' first presidential bid, his top advisers saw in Biden a potential competitor -- had he decided to run -- whose "strong connection with working-class voters," as 2016 campaign manager and former senior adviser Jeff Weaver wrote in his 2018 book, "could have created competition for rank-and-file labor votes."

Biden's opting to stay out of the race wasn't a surprise, Weaver wrote, as he recalled watching the vice president make that decision official in a Rose Garden speech, President Barack Obama at his side, in October 2015. Listening to Biden's remarks during lunch at a Washington bar that day with Tad Devine, a top consultant to Sanders in 2016, Weaver was struck by Biden's messaging.

"He decried income inequality, called for free college tuition, criticized the political establishment, and on and on," Weaver wrote. "Tad looked at me and said, 'Holy sh*t! That's our message. That's what we're running on.' Indeed it was."

Nearly five years later, after Sanders came up short a second time, Weaver and other former aides announced in April the formation of a new super PAC dedicated to growing support for Biden with Sanders' diverse young base of progressive voters.

"In 2016, I think those of us who thought Trump could win still thought that he would lose. That obviously turned out not to be the case," Weaver told CNN on Friday, adding he expected the 2020 race would, similarly, be decided on the margins. He also offered an assessment shared across much of Bernieworld: that Biden was more malleable, on policy particulars, than many on the left appreciated.

Weaver's successor as campaign manager, Shakir, argued the same -- that Biden, hardly an ideologue, had room to maneuver as he worked to grow his coalition.

"Biden, in the manner in which he campaigned and who he is, has left a lot of room for policy development. He did not campaign on a robust policy platform," Shakir said. "That's not how he won."

Before Weaver left the Sanders campaign to launch his new group, he and Shakir were dispatched by Sanders -- who was still in the race -- as emissaries to the Biden camp.

"When Bernie was talking about suspending the campaign, he hadn't made his decision, he asked me and Jeff at the time to go and start conversations with Biden's crew to figure out how much progress we could make," Shakir said. "And I said (to Sanders), 'OK, what are your chief objectives here?' He said, 'It's very simple, We need progressive policies and progressive personnel adopted by Joe Biden.'"

The conversations that followed ultimately yielded the task forces and the kind of working relationship that Sanders and Clinton, despite some successful efforts to find compromise positions on issues like higher education, never achieved.

"This is all set against 2016, where I think that Hillary's campaign was not interested in Bernie's input and had a chip on its shoulder," a top Sanders aide said. "In this case, that's never been the attitude at any point or juncture."

A former Clinton aide from 2016 conceded that Biden has been more successful in bringing along Sanders and his allies, pointing to the public rollout of the working groups, but said there had been "genuine efforts" on Clinton's behalf "to do everything in our power to squash the dynamic that had grown during the primary."

"The Biden people went about it in a really smart way. But we tried to do that stuff in 2016 and their total resistance to playing ball just bred more and more resentment from both sides," the former Clinton aide said. "And at a certain point, the feeling (among some in the Clinton campaign) was, 'You don't get to set all the terms. The people voted for her agenda and not your agenda.'"

In a statement, Biden spokesman Andrew Bates touted the former rivals' relationship and praised Sanders and his campaign for their work.

"Joe Biden and Bernie Sanders are friends and share a steadfast belief that we need a government that will deliver for working families," Bates said. "Sen. Sanders and his team have been extraordinary partners in offering advice and support on the biggest challenges of our day, such as overcoming climate change and rebuilding the American middle class -- especially after the COVID-19 outbreak."

Sanders aides and allies are reluctant, still, to concede any role in Clinton's defeat. But in interviews for this story, they almost unanimously cited, in a list alongside the candidates' personal ties and the coronavirus crisis, "the lessons of 2016" -- as Tulchin put it -- as a key factor in the shaping relations this time around.

The fruits of the task forces, and whether Biden and his team decide to embrace them, will also go a long in way in setting an expiration date on this era of good feelings. Sanders and his inner circle are clearly committed to seeing it out, at least through the election. But the activist leaders now at the table with Biden's campaign have more complicated questions to answer -- their efforts potentially coming at the cost of credibility within their movements.

Nelson, the union leader, is a co-chair of the economic task force, said her decision to take part was simple: Sanders asked and "you never say no to being at the table."

"Look at the people who have been appointed to these committees," she said. "What you see is the bringing together of the most diverse group of Democrats that you've seen in any other space. And that is Bernie's coalition. He talked about building a new Democratic coalition and I think the task forces, whether you look at Bernie or Biden appointees, reflect that."

Karthik Ganapathy, a progressive strategist and Sanders aide in 2016, credited the Biden campaign for having the humility to openly engage and try to win over a bloc of voters -- young progressives -- that they struggled with during the primary.

Still, he warned, there are murky waters up ahead.

"Are (Biden's team) going to bring on key progressive staff? Are they going to make key commitments to the Sunrise Movement and to AOC and other folks on that task force?" Ganapathy said. "Those decisions will show me if they're seriously interested in building an on-ramp for Bernie folks to get on the train."