Bernie Sanders is weighing a 2020 presidential run, traveling the country and showing that the lefty, populist fervor that made him a surprisingly strong challenger to Hillary Clinton hasn’t gone away. In the meantime, the Democrats are gaining momentum toward retaking Congress in the 2018 midterms. What’s interesting is that the two trends don’t seem to be intersecting: so far, the blue wave isn’t a Bernie wave.

In rural western Pennsylvania, Conor Lamb won a narrow special-election upset in a heavily Republican district by running a largely centrist campaign: in favor of fracking, not in favor of single-payer health care. In suburban Chicago, incumbent Dan Lipinski, a throwback Blue Dog Democrat—anti-abortion, anti-Obamacare—won a primary in a reliably liberal district by defeating a Sanders-endorsed progressive challenger, Marie Newman. And while dozens of Sanders-inspired candidates are on Democratic primary ballots this fall, their chances generally don’t appear a whole lot better. The reasons are as varied as the 435 congressional districts, but one consistent hurdle appears to be unchanged from the 2016 Sanders-Clinton presidential battle, despite provoking so much controversy: state parties, and the Democratic National Committee, are weighted in favor of entrenched candidates and traditional big-money interest groups.

“For Tom Perez to be a disappointment as the new leader of the D.N.C., I would have had to have high expectations,” says Corbin Trent, a former Sanders operative who is now communications director for Justice Democrats, one of the most prominent groups launched in the wake of the 2016 election to try to elect progressive Democrats. “When we have a Democratic Party that won’t stand behind candidates with a huge capacity to generate grassroots donations and activity, they’re not interested in letting the democratic process shake out.”

Left, Dan Lipinski photographed speaking during the Blue Dog Coalition conference on October 4, 2017; Right, Lamb greets his supporters on election night, March 14, 2018. Left, by Bill Clark/CQ Roll Call; Right, by Drew Angerer/Getty Images.

Trent points to the state of Washington as one midterm example. East of Seattle, a seven-term Republican congressman is retiring, generating an eight-way scramble for the Democratic nomination. The early favorite, Kim Schrier, has been fending off complaints from her rivals on the left that the state party is trying to clear the field on her behalf. Two candidates backed by Justice Democrats in other Washington districts, Dorothy Gasque and Sarah Smith, have run up against bureaucratic obstacles. “The state parties are still working to put their thumb on the scales in something as basic as voter file access,” Trent says. “I had hoped that one of the lessons of 2016, especially with the D.N.C., would be that a fair fight is in everybody’s best interest. But that doesn’t seem to be the case.” (The head of the Washington State Democratic Party has said she’s staying neutral. “The D.N.C. does not get involved in congressional primaries, and the state parties operate according to their own bylaws,” a D.N.C. spokeswoman says.)

Nina Turner, the head of Our Revolution, the Sanders-founded political group, is more worried that Democrats are once again selling their ideological soul in the name of racking up political victories, and will end up repeating the same lack of enthusiasm for their candidates that helped elect Donald Trump. “People say Lamb and Lipinski show that progressives can’t win. Lee Carter, in a strong Virginia Republican state legislative district, didn’t run in the middle—he won as a democratic socialist! Randall Woodfin, in Birmingham, Alabama, ran as a progressive and won the mayor’s race!” Turner says. “I was in Flint, Michigan, last night with Senator Sanders, and the reality on the ground is very much reflective of the town hall he did. Running to the middle does nothing to help the people in Flint. Playing to the middle is not what excites people and gets them out to vote, and it is not what changes the status quo in real people’s lives.”

At the moment, however, fear and hatred of Trump seem to be motivation enough to elect Democrats in many midterm races. And Bernie Dems still haven’t broken through in many contests where they need to appeal across more diverse geographic and demographic terrain; Sanders himself is now trying to fix his glaring weakness with black voters. “The Bernie crowd went all in against Ralph Northam last year in the Virginia governor Democratic primary—and lost,” says Congressman Hakeem Jeffries, a New York Democrat. “And Northam, the more centrist candidate, went on to victory in the general in November, so it’s obvious the Democrats chose the most appropriate candidate. The progressive agenda should absolutely be respected as important to the future of our nation. But it remains to be seen how potent a force the left will be in primarying Democrats. And I think we’re close to being able to say that the swing to the left has been overhyped and is not electorally effective.”