“There's a lot of candidates talking about what he talked about last time,” said Rich Gulla, the president of SEIU 1984, which represents the state’s employees. “Look at the field and look at the polling. I could talk to a dozen different members and get a dozen different responses on who they like. There's just too many in the field right now to narrow that down.”

Even as Sanders remains a top-tier contender in New Hampshire, the resistance of the state’s labor movement underscores the challenge he faces four years after he thrashed Hillary Clinton here with 60 percent of the vote.

The Vermont senator had developed close ties with labor leaders in the state well before his 2016 victory, including being invited to headline the annual AFL-CIO Labor Day breakfast so often that local Democrats privately complained they weren’t being offered the top spot.

But now, other candidates are running on a similar agenda, and those sympathetic to Sanders’ cause said they have a strong incentive to hold back for fear of picking the wrong horse.

Joe Biden, who won the support of state and national firefighters in the spring, has long been popular in the labor movement. Elizabeth Warren is also seen as a strong labor candidate, though she has not yet secured an endorsement from a New Hampshire union.

More than a dozen New Hampshire labor leaders said Sanders no longer has a monopoly on issues important to them like he did in 2016.

This year, Gulla said his union may not endorse a candidate before the primary, even though Sanders has now done two major events with members in the last few weeks.

Likewise, the state chapter of the International Brotherhood of Electrical Workers — which endorsed Sanders as early as fall of 2015, then vigorously campaigned for him for more than four months — is sitting it out this year.

“Last time, it was a real strong push from the membership to go out and endorse Bernie,” said Denis R. Beaudoin, the business manager, adding there is no “big push” to endorse anyone this election: “Everybody is working, we’re all busy.”

Labor was a crucial part of Sanders’ grass-roots coalition that Clinton’s campaign struggled to compete with, eventually losing to him in New Hampshire by more than 22 points.

“To have one of the largest unions in the state come out against their national leadership and endorse Bernie Sanders over Hillary Clinton made a huge difference in the outcome,” Kurt Ehrenberg, Sanders’ former New Hampshire political director. “It sent a signal not only to the progressive community that Bernie was for real but to the entire country that this was really going to happen, and we’re still feeling the reverberations of that today.”

Labor isn’t ditching Sanders so much as it is staying out of the primary fray. New Hampshire is following a national trend, which has seen all but a handful of unions staying out of the race. Only Biden has a large union in his camp, the International Association of Fire Fighters, but that endorsement was made by the union’s national leadership in March.

Sanders secured the endorsement of the state’s postal workers union, which represents just under a thousand people. But even that endorsement didn’t stem from a groundswell of membership support. Instead, it was a member of Sanders’ local steering committee, Janice Kelbe, who realized recently the union hadn’t endorsed yet. She made a motion in front of a union meeting recently and it was unanimously approved by the members in attendance, about 40 people.

Sanders is leaning on long-standing relationships to shore up his support, continuing to make calls to union activists to make his case. The campaign has also tasked several staffers at the national and regional levels with boosting his labor backing, including Kevin Cooper, the deputy national political director, and Sheila Healy, the New England labor outreach director.

“We didn't do steak-and-potato dinners [in 2016], but he's doing a lot of things different this time,” said Julia Barnes, Sanders’ New Hampshire state director during the last election. “There's a much more significant political outreach program this time around.”

On an operational level, Barnes said union members who showed up to support the 2016 campaign after an official endorsement from their union powered the campaign’s volunteer operation.

“Our labor brothers and sisters are amazing organizers and exceptional volunteers and adding their gusto to our operation was amazing,” she said. “It was like being in a really tough fight and then seeing really great friends show up to fight with you right and there was an exceptional morale boost and camaraderie in their connection to our campaign.”

Barnes is still a Sanders supporter but is not working for him this election.

Sanders’ current state director downplayed the lack of official union endorsements.

“My understanding it's a good thing that the unions are having a more inclusive and transparent process to make sure that their endorsement is reflective of their membership,” said Shannon Jackson. “We're trying to get (the state employees) endorsement just as much as anybody else.”

Inside labor halls, members are divided about who to support. In interviews, labor leaders said they have gone out of their way not to push endorsements for fear of upsetting their dwindling and divided membership.

Those local officials said they are more focused on making sure their members are informed, instead of attempting to flex their muscle in the primary. They are going out of their way to make sure their meetings with candidates are not only open to membership, but recorded so that the rank-and-file can watch later.

New Hampshire House Majority Leader Doug Ley, who also serves as president of the state’s American Federation of Teachers chapter, said it is clear labor will not have a unified voice this election.

“There are other candidates that are honestly cutting into Bernie's support,” he said, adding that Warren appeals to the same demographic.

“You need almost like a razor blade to separate some of these folks on issues,” he said. “It's really not much of a difference on the kinds of issues of concern for us.”