Minnesota Rep. Keith Ellison hadn’t been campaigning for chair of the Democratic National Committee for more than a week before veteran party officials began publicly saying he wouldn’t have time to both hold the position and serve as a congressman.

Ellison then announced that he’d step down from congress if he won the DNC race. But almost as soon as he did so, a new chorus of objections to his candidacy began: top Democratic sources told reporters they were growing concerned about Ellison’s alleged ties to the Nation of Islam and radical black Muslim organizers in the 1990s.

To Ellison’s supporters — largely from the Bernie Sanders wing of the party — these attacks looked like ugly smears cynically deployed to derail their candidate. But they’ve also made Ellison’s backers feel like they’re shadow-boxing an elusive foe — that his opponents were throwing up objections in bad faith rather than plainly identifying their problem with his beliefs or proposed platform for the party.

Their frustrations are well-founded. The 2016 Democratic primary between Sanders and Hillary Clinton saw major substantive divides; there were huge and obvious gaps between the candidates over taxes, foreign policy, healthcare, and a host of other critical policy issues.

The race for DNC chair, by contrast, has become largely a power struggle between factions — but one lacking a clear contrast of ideas.

Many Democrats skeptical of Sanders have rallied behind Tom Perez, one of the most progressive members of the Obama cabinet. Making Perez the alternative to Ellison may be intended as an olive branch to grassroots progressives. But it could also backfire badly, by exacerbating Sanders' allies distrust of a party that needs their support now more than ever.

Ellison emerged early as a unity choice

Shortly after Ellison announced his DNC chair candidacy, Sanders quickly endorsed him. So did Sen. Elizabeth Warren, who is typically seen as ideologically aligned with Sanders but who didn’t endorse in the primary. So did the presidents of the American Federation of Teachers and the American Federation of State, County, and Municipal Employees — two of the biggest and most politically influential Clinton-endorsing unions. That set the stage for a potential ideological battle that would set a range of progressives forces that had diverse views on the primary against someone from the more centrist wing of the party.

Ellison was also endorsed by Chuck Schumer, a Clinton endorser who frequently typifies the kind of close ties to Wall Street that Sanders criticizes, but who is trying to wield together a unified Democratic Senate caucus to do battle with Donald Trump.

Schumer backing Ellison seemed continuous with a larger strategy in which Sanders and some Democratic Party leaders are seeking a rapprochement that will shepherd as many of Sanders’ grassroots supporters as possible into the Democratic Party tent. Polls show that Sanders remains very popular with the public, and he has amassed a hardcore following that includes both left-wing ideologues and independent-minded voters who like that Sanders rejects “establishment” politicians.

But as I discovered in Philadelphia when interviewing Sanders’s voters at the DNC convention, Sanders can’t merely declare that everyone should back Democrats and expect all his fans to follow — some were even quick to call him a turncoat merely for endorsing Clinton.

One concession has been a new post for Sanders in the party’s Senate leadership. Giving the DNC chair position to Ellison, who endorsed Sanders and has been loyal to the Vermont Senator’s cause, fits this pattern. And it’s one reason Sanders has been pressing hard and devoting time to campaigning with Ellison: It helps sell the argument to Berners who remain skeptical that the Democratic Party is the right vessel for their agenda.

The DNC chairship looms large in Bernieworld

The DNC chair position looms large — perhaps larger than it should — in the minds of Sanders supporters. Many Sanders supporters believe that former DNC Chair Debbie Wasserman-Schultz helped stack the deck against Sanders — and that this was a key reason Sanders lost the primary.

Few people outside the hard-core Sanders circle think this is true, but to an extent that’s the point: precisely because many Democrats think Sanders supporters overstate the institutional power of the DNC chair, this is a smart concession to make to them. Putting an unassailable Sanders ally at its helm is an easy way to demonstrate that the party is reformed and no longer “rigged” — especially if you don’t believe it was ever rigged in the first place.

The emergence of Tom Perez mutes ideological conflict

The most obvious alternative to a stalwart progressive like Ellison would have been for Sanders’ critics in the Democratic Party to elevate a standard-bearer of the party’s more moderate wing. Missouri Secretary of State Jason Kander, for example, ran far ahead of Hillary Clinton in the red state and would have been a plausible centrist alternative to Ellison.

Instead, Ellison’s strongest opponent looks to be Perez. Four Democratic governors are backing him, he’s received endorsements from a few labor unions, and some Sanders allies, bolstered by reporting from the New York Times, feels the Perez boom is being fueled by Obama’s political team — though the White House denies this.

But Perez doesn’t present much of an ideological break from Ellison. He was an ardent foe of the Iraq War within weeks of it being declared; he has longstanding connections to the labor movement and the “Fight for $15” minimum wage campaign; he’s widely considered Obama’s most liberal Cabinet member; union leaders have loved his work.

Nor are their stated agendas, both geared toward more comprehensive and more granual organizing, particularly different. Perez calls for a DNC strategy in every zip code, while Ellison has called for one in every county.

Ellison allies are attacking Perez for supporting the now-dead Trans-Pacific Partnership trade deal as a member of the Obama cabinet. Ellison, like the vast majority of congressional Democrats, opposed it from the beginning. The pact is, however, completely dead and in a practical sense Perez had no alternative to backing his boss on this question.

In many ways what really aggravates Sanders’ allies about the push for Perez is the very absence of any kind of clear strategic or ideological gap between Perez and Ellison. If a big part of the case for Ellison is that installing a well-known Sanders ally at the DNC would help unify the party, then the essence of the case for Perez seems to be a desire to freeze Sanders’ circle out.

A Perez win will likely fuel more bitterness

In almost any other context Perez’s ascension to the DNC chairmanship would be heralded as a major victory for the party’s progressive wing. Had Hillary Clinton won the election, for example, progressive groups were prepared to press her to tap Perez for Attorney-General or some other high-profile role.

But this race isn’t happening in a vacuum.

Perez & Ellison are both strong candidates. IMO the party needs someone unapologetic, innovative, very left & dedicated to a diverse base. https://t.co/HgvcZynpnQ — Jill Filipovic (@JillFilipovic) December 15, 2016

A Perez win now would be seen as a major insult to Sanders and his supporters. Precisely because there isn’t an overt policy void between the two leading contenders, the Perez candidacy looks to Sanders backers like an effort to punish Ellison for having supported Sanders in the primary — or, at the very least, to make sure that those connected to Sanders personally are shut out of power.

That, in turn, reignites old grievances from the primary about interest groups being pressured to endorse Clinton — even though Sanders’ record on their issues was solid — out of fear of reprisal. Many Bernie loyalists believe that this kind of hardball politics — paired perhaps with bias at the DNC — is the reason that Sanders lost the primary, and they also believe that Sanders would have won in November. In their view, this is exactly the kind of “rigged” establishment politics that put Trump in the White House. And now a shadowy cabal of insiders wants to do it again.

Clinton supporters find this chain of reasoning preposterous — often so preposterous that they don’t recognize many people believe it. But they do. Ellison as chair would go a long way toward redressing the grievances accumulated up over months of a long, bitterly-fought primary. Perez as chair would almost certainly exacerbate them.