New York Democratic gubernatorial candidate Cynthia Nixon addresses a news conference in Albany, N.Y., on March 26.  (Frank Franklin II/Associated Press)

On Friday morning, New York gubernatorial hopeful Cynthia Nixon made a quick stop in Washington to address 450 Democratic candidates at a pre-election training session hosted by the Progressive Change Campaign Committee. They interrupted her with cheers, more than two dozen times, as the woman challenging Gov. Andrew M. Cuomo (D) described a rigged and swampy Democratic Party.

“We’re going to show the world that in the divide-and-conquer era of Donald Trump, progressives will come together and lead our nation forward,” said Nixon.

Hours later, Cuomo was busy dividing — though not conquering — one of Nixon’s biggest potential sources of support. Two labor unions that had helped build the Working Families Party, which is holding its convention this weekend in Albany, bolted from the party over the possibility that it would endorse Nixon over Cuomo. By the end of the day, Cuomo said he would not seek the party’s nomination; in New York’s “fusion” system, that meant he’d be relegating Nixon to third-party spoiler status unless she beats him in the Democratic primary.

It was a tricky day for the ongoing project of moving the Democratic Party to the left. The PCCC, founded in 2009 to elect more left-wing populists, had never brought so many candidates to a training session. Most were running for state and local offices; a few were seeking seats in Congress. There was plenty of passion for victory, but little love for the party itself, as Rep. Keith Ellison (D-Minn.) found when he delivered a Friday morning speech.

“I ran for chair of the Democratic National Committee, and I ended up being deputy chair,” said Ellison.

“Should’ve won!” shouted one candidate in the audience, who was cheered by the people around him.

“Let me tell you this: In this life, you’ve got to be all in for the team,” said Ellison. “It may not come out your way, but the passion and the issues and the people you’re fighting for: They’re still there! What, am I going to say ‘I’m out of here?’ No.”

In training sessions, most of them kept off the record, candidates were trained on how to avoid falling into traditional media frames of right and left.

“Any old blue just won’t do,” said Nina Turner, the president of Our Revolution, the group founded by Sen. Bernie Sanders (I-Vt.) after the 2016 presidential primaries.

Sanders himself spoke to the crowd on Thursday, delivering a familiar message: That the Democratic Party’s centrists were losing ground or giving up power altogether.

“What was once considered radical is now mainstream,” said Sanders, ticking off issues like a $15 minimum wage and universal Medicare coverage.

Nixon’s speech, full of attacks on Cuomo, also pointed to the current dynamic in the party. “I declared loud and clear that it is time for New York to legalize the recreational use of marijuana,” said Nixon. “This is, first and foremost, an issue of racial justice. We have to stop putting black and brown people in jail for something white people do with impunity.”

Nixon had first made those remarks about marijuana at a fundraiser, which was then reported by the New York Times. This week, Cuomo — who maintains a 3-1 lead over Nixon in polls — surprised the press by saying he, too, had come to view marijuana laws as out of date.

Moments like that had given PCCC-trained candidates a sense of control. In side rooms, and sometimes during sessions, candidates huddled together to strategize how they could help each others’ campaigns. A group of Oklahoma candidates, some of them teachers who had participated in the state’s waves of strikes, discussed whether it was possible to create a national organizing force for teacher/candidates, similar to organizations that exist to promote veterans.

In her Thursday afternoon speech, Sen. Elizabeth Warren (D-Mass.) — who the PCCC had urged to run for Senate in 2012 — used her own story to argue that a little dedication could turn anyone into a candidate. She also said, explicitly, that the Democratic Party would be the vehicle for those candidates’ success.

“I gave a contribution — a big one — and not just to the DNC,” said Warren. “Not just to the DSCC. Not just to the DCCC. I made a contribution to every single state party, so that they can make the grass-roots organizations that we need. I did that because I want you to win. That’s why.”