After Tuesday, will Bernie Sanders’ tone pave way for concession?

Sen. Bernie Sanders at a campaign stop on April 21 in Scranton, Pa. (Photo: Jake Danna Stevens/The Times & Tribune via AP)

Polls suggest that Sen. Bernie Sanders is poised to lose Maryland and Pennsylvania in key races Tuesday, raising questions about whether the progressive candidate — who continues to raise millions of dollars from his passionate supporters — will adopt a more unifying tone as his chances for the Democratic nomination fade.

During last week’s New York primary, Sanders sounded a defiant note as he lost the delegate-rich state, fiercely criticizing rival Hillary Clinton in an hourlong speech at Penn State University. He blasted her paid speeches to Goldman Sachs as his supporters booed heartily. Sanders’ campaign manager appeared on MSNBC later that night, arguing that the campaign would fight all the way to July’s convention to woo superdelegates away from Clinton.

By Sunday, however, Sanders was already striking a more conciliatory note. On “Meet the Press,” he acknowledged that his campaign’s path to victory was “narrow,” but said he still hoped to win. Though he stressed he was not writing his campaign’s “obituary” yet, he spoke of his run in the reflective manner of someone who sees that the party could be nearing an end. Sanders said he’s “proud” he brought “millions of young people” into the political process.

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But when pressed about whether he would encourage his young supporters to back Clinton, the senator said the primary responsibility will be on Clinton, not him, to convince people that “she is the kind of president this country needs to represent working people.”

As Sanders shifts his campaign away from a fight for the nomination and toward a fight for his supporters’ more progressive values to have a louder voice within the Democratic Party, it remains to be seen whether and how quickly his rhetoric against Clinton will soften.

Howard Wolfson, a Democratic strategist who helped run Hillary Clinton’s campaign in 2008, said that Sanders finds himself in a similar position as Clinton did in the spring of 2008. She had won many states but found it mathematically unlikely that she would clinch the nomination. Still, it was hard to let go.

“It’s a little bit of a head-heart dichotomy. You are able to coldly look at the math and draw conclusions from it, but your heart tells you that you should keep going,” Wolfson said. Candidates are also surrounded by their most fervent supporters, even when they’re losing. “I remember in 2008 when Hillary Clinton would be on a rope line in the spring, she would have women come up to her and say, ‘Don’t you dare drop out.’”

At some point after the Clinton camp’s realization that the nomination was unlikely, the tone of the Clinton-Obama primary — which was in many ways more antagonistic than this current contest — cooled off. The détente came from both the Obama and Clinton camps.

“Let me tell you, it does take two to tango,” Wolfson said. “It’s important for the front-running campaign, the likely victor, to also recognize that the next real goal is about unity rather than continued acrimony. To their credit, I think the Obama campaign began to ease off the gas a little, as well.”

Clinton has already seemed to back off some of her camp’s attacks on Sanders. At her victory speech in New York, she said that more unites Sanders and Clinton supporters than divides them. But she’s going to have to do more than that to bring Sanders’ supporters into the fold. The contest between the two was at its most acrimonious just a week ago in New York, and the pair spent most of the Democratic debate in Brooklyn earlier this month shouting at each other.

Hillary Clinton at her primary night party last Tuesday in New York City. (Photo: Louise Wateridge/Pacific Press/LightRocket via Getty Images)

“It’s up to Clinton at this point to extend an olive branch,” said Matt Dickinson, a political science professor at Middlebury College.

The Clinton campaign also has to be careful not to be seen as shoving Sanders off the stage, in order to respect the campaign that he’s run and the support he’s amassed.

“She has a self-interest in giving him space, giving him time, letting him make his case,” said Bob Shrum, a veteran political consultant and professor at the University of Southern California.

Clinton knows she will be stronger with Sanders’ and his supporters’ backing, and can try to win that by meaningfully including the senator in the Democratic convention in July. She faces the daunting task of wooing Sanders without allowing him to hijack her message or drive her too far to the left before the general election.

The two may end up horse-trading. Clinton could offer key Democratic platform positions like a $15 minimum wage or a ban on fracking — as well as a prime speaking slot at the convention — in exchange for his support.

“The trick is to do that without ceding control of the party’s message to Sanders,” Dickinson said.

Shrum said he has “no doubt” that Sanders will stay in the contest until California’s primary on June 7, and will likely continue to run through July’s convention, even as his chances dim.

Shrum was Ted Kennedy’s speechwriter during the 1980 convention, when the senator refused to raise his arm in celebration when then-President Jimmy Carter clinched the nomination over him. Shrum says this convention will be nothing like that poisonous atmosphere.

“[Sanders] is probably going to go to the convention and he’ll speak at the convention, but it’s not going to be antagonistic,” Shrum said. “He’s run a spectacular campaign that no one predicted. So if it’s going to end, the other side needs to let it end in a way that gives him respect and recognition and even more so gives that respect and recognition to his supporters.”