Democratic congressional candidate Alexandria Ocasio-Cortez won’t endorse Vermont independent Sen. Bernie Sanders despite campaigning with him as a fellow socialist.

Ocasio-Cortez, who worked as an organizer for Sanders’ 2016 presidential campaign, beat longtime Democratic incumbent New York Rep. Joe Crowley in a primary last May. She declined to endorse Sanders in an interview with Politico on Thursday. Her campaign’s communications director, Corbin Trent, said that "She’ll see what the field looks like," and that "she’s focused on 2018, [Bernie’s] focused on 2018. We’re all focused on 2018."

Although Sanders did not endorse her run against Crowley, he has campaigned with Ocasio-Cortez multiple times since her victory.

“I’ve had a few people reach out and be like, ‘How do I reach out to Warren?’” said an unnamed former Sanders staffer. “Some of the Sanders stalwarts, not just staff but high-profile supporters, aren’t necessarily in the bag for 2020.”

“All the former staff I’ve talked to agree Bernie should focus on making sure the nominee is someone who continues what he started,” Sanders’ former digital advertising director Keegan Goudiss said to Politico. “It’s a sure thing that he will be able to influence 2020 from the outside. But if he decides to run, I doubt many former staffers will return unless directly asked to. Either way, he misses capturing energy if he doesn't decide soon.”