(Bloomberg) — As tensions were escalating between Bernie Sanders and Democratic Party leaders over the chaos caused by his supporters at a Nevada convention, Dick Durbin got an unexpected call from the Vermont senator.
Durbin, the No. 2 Democrat in the Senate, came away from the conversation on Wednesday convinced that Sanders, who has all but lost the presidential nomination battle to Hillary Clinton, understands the need for party unity and will do his part to defeat presumptive Republican nominee Donald Trump.
"We talked about the demonstrations and such," Durbin said Thursday in an interview. "I am convinced, as Bernie has said repeatedly, he is going to be on the team to defeat Donald Trump. I don't have any question in my mind."
But such niceties mask growing impatience among Democratic Party leaders. And the behind-the-scenes assurances contrast with the defiant posture Sanders has adopted in the campaign, promising to take his fight for the nomination into the Democratic convention in July and calling the rules of the contest rigged.
Many in the Democratic establishment are privately seething over Sanders continuing to paint Clinton as the candidate of Wall Street and business and the party as corrupt. They are increasingly concerned that his refusal to back down will lead to enduring party fissures and potentially cost Democrats the White House. It may also ultimately threaten Sanders' goal of shaping the party's future and returning to the Senate with greater influence than he's ever had before.
Sen. Tim Kaine of Virginia, a Clinton ally and former chairman of the Democratic National Committee, indicated that patience is wearing thin.
"It is time for the rhetoric to start to come together around helping our team win,'' he said in an interview. "I think it was very plain after the results of this week that Hillary will pass the threshold, and likely by a lot. She'll be the nominee under the rules that everybody understood were the rules when we started this."
Echoing recent statements by Clinton, Kaine recalled her decision at about this same point in the 2008 nomination race to tone down attacks on then-Sen. Barack Obama even as she campaigned to the very end. "I think it's time for Bernie to do that," he said.
Trump, for his part, is salivating at the prospect of Democratic divisions boosting his chances of defeating Clinton.
"I believe that a large percentage of his [Sanders'] people vote for Trump. You watch," Trump told cheering supporters Thursday at a campaign event in Lawrenceville, N.J. "The one thing he's right on is trade."
Clinton claims victory
Clinton on Thursday delivered a direct message to Sanders and a challenge to his repeated assertion that he can still change the trajectory of the race.
"I will be the nominee for my party,'' she said in an interview on CNN. "That is already done, in effect. There is no way I won't be.''
The response from the Sanders campaign reflected the content and tone of the argument Sanders has been making in the final stages of the campaign. Saying polls show Sanders is a stronger candidate against Trump, spokesman Michael Briggs said in a statement that "it is clear that millions of Americans have growing doubts about the Clinton campaign." He noted that Clinton lost recent primaries to Sanders in Indiana, West Virginia and Oregon.
Members of the Democratic establishment are motivated to get out the message that the party will be unified coming out of the convention in Philadelphia, in order to calm donors and to make sure they move past internal disputes and shift focus to turning out voters to defeat Trump in November.
But Sanders has incentive to stay in the race as well. He and his strategists have said they want to maximize his leverage in the primaries to pursue a wish list of reforms at the July convention, which may include eliminating unpledged superdelegates and allowing more "open" primaries in which independents can vote, along with changes to the party platform that call for reforms like single-payer health insurance and breaking up the largest banks.
Still, his conduct is bringing intra-party tension closer to a boiling point, pitting his most enthusiastic followers—some of whom say they'd refuse to vote for Clinton in the general election—against Democrats eager to shift gears to the general election.
"It is incumbent on all of us to calm the waters as opposed to feeding the tension. Hillary has every right to say she's going to win the nomination,'' said Randi Weingarten, president of the American Federation of Teachers, a Clinton supporter and a Democratic superdelegate to the convention. "But I think you see a lot of discomfort with tensions as high as they are now. The stakes in this election are too high."
Sanders has reached out to multiple Senate colleagues in an attempt to assuage them. Among them is Sen. Barbara Boxer of California, whose keynote speech at the Nevada state Democratic convention last weekend was disrupted by rowdy Sanders supporters in a situation she described as frightening and out of control.
Boxer said she conveyed her concerns to Sanders in "a really nice talk" with him Tuesday. "I told him how bad it was in Nevada. He said he was distressed about it, and he expressed chagrin about it. I told him 'Bernie, you need to get a hold of it,' and he said he would.''
"He said, 'I can't believe my people would do this,'" said Boxer, who is stepping down from the Senate in January. "He got the point."
There are nine primaries or caucuses left on the calendar. Clinton has 96 percent of the total delegates needed to clinch the nomination, according to an Associated Press estimate Wednesday. Sanders has 64 percent. He'd need to win about two-thirds of the rest of the pledged delegates to pull even with Clinton by the end of the nominating race, a herculean task given that delegates are awarded proportionally on the basis of victory margins. He's making his last stand on June 7 in California, the biggest prize of all with 546 delegates.
Despite the party divisions, many Democrats are trying to stay optimistic. Sen. Chris Murphy of Connecticut predicts the divisions between Sanders supporters and Clinton supporters will be erased over time.
"Frankly, Donald Trump is going to be a fantastic unifying force within the Democratic Party,'' he said. "I just don't see this in the crisis terms that many people see it."
For Sanders, the decision on how hard to push carries implications for his future in the Senate, where he's currently next in line to chair the influential Senate Budget Committee. Alienating his colleagues has the potential to jeopardize that standing and turn him into more of an agitator in the vein of Republican Ted Cruz, who uses his grassroots support as a sword against his party.
Kaine nudged Sanders to use that influence for good.
"He'll have a lot of torque here," Kaine said. "Not just because of his seniority but because of the way he's run his campaign. It's going to give him tremendous influence."
—With assistance from Margaret Talev and Steven Dennis in Washington
Have you followed us on Facebook?