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Both Democrats in the race for Texas’s 28th congressional district received important endorsements on Friday. The conservative incumbent, Henry Cuellar, was endorsed by the Koch-funded LIBRE Initiative Action. On the same day, his left-wing primary challenger, Jessica Cisneros, received a set of endorsements from an altogether different source: the labor movement.

In a Friday morning press release, the Cisneros campaign announced that it had the backing of the American Federation of State, County and Municipal Employees (AFSCME), the Service Employees International Union Texas (SEIU), and the Texas American Federation of Teachers, among others. Another major labor group, the Texas AFL-CIO, previously endorsed Cisneros in January. In December, pro-choice groups — including Planned Parenthood Action and NARAL Pro-choice America — endorsed Cisneros over Cuellar, who is anti-abortion. Cisneros, a 26-year-old immigration attorney, thus enjoys wide support in the progressive world. Cuellar, meanwhile, refuses to debate her.

After pro-choice groups backed her insurgent campaign in December, Cuellar spokesperson Colin Strother adopted a dismissive tone. The organizations, he told NBC News, were “focused on some kind of a purification ritual that does nothing other than feed their ego and their donor base.” But what may look like a purification ritual to Cuellar looks increasingly like good politics to lots of other people. By January, Cisneros had raised nearly $1 million in her quest to unseat Cuellar — a major show of force for a first-time, left-wing candidate. To many, Cisneros represents the party’s future.

But some powerful Democrats disagree. The race between Cisneros and Cuellar has exposed deep fissures in the national party that will persist long after the primary ends. Speaker Nancy Pelosi and Rep. Cheri Bustos, the head of the Democratic Congressional Campaign Committee (DCCC), backed Cuellar early, and they back him still. The DCCC’s vendor blacklist, intended to block consultants and outside firms from working for primary challengers, also protects Cuellar, though it wasn’t enough to prevent significant portions of the progressive movement from supporting Cisneros. A similar dynamic has emerged in Illinois, where Marie Newman challenges incumbent Dan Lipinski. Like Cuellar, Lipinski is anti-abortion; also like Cuellar, he enjoys the support of party leadership. The Newman campaign said previously that the DCCC’s blacklist did deter some vendors from working with them. But Newman has since picked up major labor and reproductive rights endorsements, including the SEIU Illinois State Council and the Planned Parenthood Action Fund.

In each primary race, Pelosi and Bustos have pitted themselves against unions and the pro-choice movement. It’s an uncomfortable position for any Democratic leader to occupy, and it promises trouble later down the road. Neither Cuellar or Lipinski represent conservative districts. Voters in both districts supported Clinton in 2016; whoever wins the Democratic primary in either district is very likely to enter Congress in November. There is no good reason, in other words, for party leaders to back a pair of anti-choice men over a pair of pro-choice women. In doing so they keep alive a strategy from an earlier, failed age of Democratic politics. The idea that the party ought to compromise on some core issues in order to win moderate districts may well create a big tent. But it hasn’t helped the party maintain a grip on power, either in the states or in Congress.

Instead, Pelosi and Bustos have made themselves look weak. What good is the DCCC’s blacklist if it doesn’t work? And how trustworthy is the party as an ally to pro-choice groups and to unions if its leaders ignore the preferences of both movements? Cisneros stands a legitimate chance of defeating Cuellar. The incumbent himself seems to realize this, since he’s refused to debate her and is running attack ads against her. If she does win, she, like insurgents before her, will have to reckon with a party whose leaders stubbornly refuse to change. That bodes ill for the future of progressive policy, and for the future of the party itself.