Bernie Sanders has a superdelegate problem again. He needs a solution.

Though he’s looking in a stronger position to win the nomination in 2020 than 2016, he may still come up short of the delegate majority needed to win. Though the race is still fluid, it’s possible that superdelegates — the thing Sanders supporters spent so much time criticizing in 2016 — could hand the nomination to former Vice President Joe Biden. Or, Sanders may have to convince them that he should be the party’s standard-bearer against President Donald Trump.

Superdelegates, current or former elected officials and party leaders, aren’t bound by the votes from the primary election. Winning these free agents is essential if no one candidate wins the number of delegates needed outright.

For now, Sanders allies are hoping convention night drama goes no further than the first ballot, where superdelegates won’t have a say. And some are already urging Democratic Party leaders to prepare to avert superdelegates running amok on the second ballot.

The stance from party leaders should be, “We have to figure this out, we’re not going to turn the convention into a shitshow, because that’s what a second ballot will be,” said vice-chair of the Democratic National Committee’s Unity Reform Commission Larry Cohen, who is also board chair of the Sanders-affiliated group Our Revolution.

Sanders’s team is making the case that, if he is the clear leader among pledged delegates, the superdelegates must back him — that the backlash would be too great if the Democratic elite were seen as stealing the nomination from him on the convention floor.

“If there was a scenario where the plurality leader was denied because a lot of moderates get together, it runs the risk of splitting the party and hurts our chances of keeping the House and the Senate,” said Rep. Ro Khanna (D-CA), another Sanders national campaign co-chair and a superdelegate.

Instead, the battle lines are already being drawn. The New York Times interviewed more than 90 superdelegates and found the overwhelming majority were prepared to deny Sanders the nomination at the convention if he had not won a delegate majority during the primary. Moderates are already coalescing around Biden after his win in South Carolina, and Biden had an excellent night on Super Tuesday, winning at least nine states as of late Tuesday night.

If the race between Biden and Sanders is still close this summer, it’s looking like a convention floor fight would be fierce.

“If Joe Biden were to be the candidate who went in with 47 percent of the delegates ... there’s a perception that everybody would be fine in that situation voting for Joe Biden, but because it’s Bernie Sanders, they’re not going to do it,” said Rep. Pramila Jayapal (D-WA), another of Sanders’s national campaign co-chairs who is also a superdelegate, told Vox in a recent interview. “I think that would be an enormous problem.”

Sanders doesn’t just need to win the votes and the delegates. He also has to win over the party.

The new rules for Democratic superdelegates in 2020, briefly explained

Crucially, the rules have changed around superdelegates since 2016, largely at the request of furious Sanders supporters. The Democratic National Committee’s rules explicitly state that a candidate must secure a majority of the nearly 4,000 delegates up for grabs in order to secure the nomination. Previously, a Democratic candidate could do so through a combination of winning state-level delegates and superdelegates. Superdelegates made up a small but still considerable part of the delegate math: There are about 800 of them, compared to the 4,000 or so “pledged” delegates who are won in the primaries and caucuses.

But when superdelegates appeared to hand Hillary Clinton the nomination before she officially secured enough from primary elections in 2016 — 571 for Clinton versus just 45 for Sanders, to the objection of many Sanders supporters — the party changed its rules. Now superdelegates only come into play after the first round of voting at the convention.

Under the rule changes, they would no longer be allowed to vote on the first ballot, only on a second ballot and other subsequent votes if no candidate had won a delegate majority. Josh Putnam broke down the new rules at FrontloadingHQ:

1. If a candidate wins 50 percent of the pledged delegates plus one during or by the end of primary season, then the superdelegates are barred from the first ballot. 2. If a candidate wins 50 percent of all of the delegates (including superdelegates) plus one, then the superdelegate opt-in is triggered and that faction of delegates can participate in the first (and only) round of voting. 3. If no candidate wins a majority of either pledged or all delegates during or by the end of primary season, then superdelegates are barred from the first round and allowed in to vote in the second round to break the stalemate.

Sanders’s supporters argue that if he is the clear leader in delegates at the Milwaukee convention, then he must be the nominee. Anything else would risk a party fracture.

But those aren’t the rules. And if Democrats end up brokering their nomination in the open, on the floor of the DNC, it would be a test of the Vermont senator’s ability to execute the back-slapping and arm-twisting he normally seems to loathe.

The biggest thing standing in the way of this theory is the margins. Sanders has a much stronger argument to win over superdelegates the closer he is to a majority.

If Sanders and Biden finish a close first-second before the convention, with neither of them winning a majority, superdelegates could help hand the nomination to the second-place candidate. Or if Biden is narrowly ahead, they could push him over the top. And some of them are openly threatening to do exactly that.

The Sanders campaign has a multi-pronged strategy for superdelegates

There are two schools of thought in the Sanders campaign around a contested convention. One is what Sanders himself has projected publicly, that he should be the nominee even if he falls short of the required majority and just has a plurality of delegates.

“If you go in there with a strong plurality, that person should be the nominee,” Jeff Weaver, Sanders’s senior adviser, told the Atlantic.

The thing is, nobody knows yet what a “strong” plurality is. Jayapal would say only that Sanders with 49 percent of the vote and the second-place candidate with 20 percent is a very different situation from Sanders being in first at 43 percent and the next candidate right behind him at 41 percent.

Unofficially, some think Sanders should negotiate a deal with fellow progressive Sen. Elizabeth Warren to build a left-wing coalition and secure the majority of needed delegates on the first ballot — without getting superdelegates involved. This is possible because DNC delegates are not legally bound to their candidate, as Republican delegates are, and there are not really firm rules for what they must do if there is not a clear primary winner.

“It needs to be first ballot, if necessary it needs to be negotiated out,” said Cohen, the board chair of Our Revolution. “I think it hopefully looks like Warren and Sanders and their elected delegates. We have done work to keep those bridges very much alive.”

Other groups are calling on Sanders and Warren to commit their delegates to one another in the event of a contested convention. Of course, the potential snag in this plan is Warren’s paltry delegate count so far; she’s amassed just 34 delegates so far, per Decision Desk’s latest count.

“Sen. Warren has been an ally of the progressive movement throughout her entire career. But I hope she stops attacking Sen. Sanders and publicly commits to give her delegates to him if he has more votes to ensure a progressive wins the nomination. I’d say the same to Bernie,” said executive director of Justice Democrats Alexandra Rojas in a statement to Vox.

An eventual convention floor fight would depend on a lot of variables. Putnam at FrontloadingHQ noted a few:

How big the margin is between the first- and second-place candidates

Whether the superdelegates team up with delegates for other lower-performing candidates to form a majority

What rule changes might be made at the convention

Whether delegates can agree on a consensus candidate

And he threw out another wrinkle: “All bets are off in a contested environment,” Putnam says. “That has not been tested in the post-reform era. But that would add an additional layer of chaos to it all.”

For any candidate who isn’t the delegate leader coming into the convention, they’ll have to make the pitch — to superdelegates, to pledged delegates, to the party at large — that they nevertheless deserve the nomination. Warren’s pitch would likely be that she’s been a leader at developing policy in the 2020 primary, and she is already many voters’ second choice, crossing a broad coalition in the party.

There’s no grand plot to team up and beat Sanders — yet. But his opponents aren’t ready to hand him the nomination.

Why some superdelegates are so nervous about a Sanders nomination

The potential for a superdelegate showdown came into full view last week when the New York Times posted their story summarizing interviews with nearly 100 superdelegates. They were unsparing:

Dozens of interviews with Democratic establishment leaders this week show that they are not just worried about Mr. Sanders’s candidacy, but are also willing to risk intraparty damage to stop his nomination at the national convention in July if they get the chance. Since Mr. Sanders’s victory in Nevada’s caucuses on Saturday, The Times has interviewed 93 party officials — all of them superdelegates, who could have a say on the nominee at the convention — and found overwhelming opposition to handing the Vermont senator the nomination if he arrived with the most delegates but fell short of a majority.

“Bernie wants to redefine the rules and just say he just needs a plurality,” Jay Jacobs, chairman of the New York State Democratic Party, told the Times. “I don’t think we buy that. I don’t think the mainstream of the Democratic Party buys that. If he doesn’t have a majority, it stands to reason that he may not become the nominee.”

Sanders supporters interpreted that as an establishment sector of the party feeling threatened by an insurgent candidate.

“He has always taken on systems that he feels are unjust and I think that includes the way politics are structured today,” Jayapal said. “A political revolution, as he talks about it, threatens people who are part of the existing system and I think that is part of what’s going on.”

The official story from the Sanders-skeptical superdelegates is simple: Sanders might lose to Trump and also risks Democratic losses in the House and Senate. They cite Democrats in swing districts — like Rep. Joe Cunningham in South Carolina, who has already distanced himself from Sanders — as evidence.

Majority Whip Jim Clyburn just used the phrase “down-ballot carnage” to describe the concern he’s hearing about a potential @BernieSanders nomination in an interview on CNN. — Averi Harper (@AveriHarper) February 28, 2020

It is true more moderate candidates historically do better than the rigidly ideological. And in the 2018 midterms, House candidates who ran on Sanders’s Medicare-for-all platform fared worse than those who stuck to a center-left message about building on Obamacare.

But whether that is true on the presidential level is still unknown. Some election prognosticators, like the Cook Political Report’s Dave Wasserman, think these concerns are overblown. Sanders seems to fare just as well against Trump as the ostensibly more “electable” candidates like Biden — and he has the potential to overperform Clinton in working-class districts.

But the point is, we don’t yet know what will happen, and Sanders supporters think the speculation is irresponsible. Jayapal pointed out that House Speaker Nancy Pelosi has not echoed these concerns, saying instead she’d be comfortable if Sanders were the party’s presidential nominee.

“To fear-monger and say we’re gonna lose the House if Bernie Sanders is the candidate, I could say that about Michael Bloomberg right now,” Jayapal says. “The thing that will drive the party into disarray and fracture us potentially in irreparable ways is if we start trying to control the election results now and putting thumbs on the scale in ways that will be seen as not respecting what voters are telling us.”