After winning the election in 2008, Barack Obama, before being sworn in as president, effectively shuttered the unprecedented grassroots army his campaign had mobilized. The decision, which took his 10 million-plus donors and volunteers off the political battlefield, is regularly cited today as having hampered his first-term agenda. Bernie Sanders, when asked on Saturday afternoon whether he would make a different decision if he were to win the presidency in 2020, said, “Yes, I absolutely would.” Sanders, along with Rep. Alexandria Ocasio-Cortez, D-N.Y., sat down for an interview with The Intercept ahead of his rally in Queens, New York — his first since having a heart attack in Las Vegas earlier this month — and spoke in granular detail about what political revolution means to him. While he was eager to expound on the ability of an organized, working-class movement to overpower structural obstacles, he stopped short of endorsing new congressional primary challengers. However, he did say that he plans to become more involved in such challenges in the near future.

Sanders and Ocasio-Cortez discussed the Espionage Act, Syria, Joe Biden, monopoly politics, and why Ocasio-Cortez endorsed Sanders over Elizabeth Warren. Watch the full interview here. In contrast with Obama’s strategy, Sanders said that he met with the former president and shared his thoughts directly. “I’m a great fan of Barack Obama, who’s a friend of mine. He and I have actually discussed this very issue. His view is, it’s hard to do it,” said Sanders. “I understand that. But the essence of my politics, and I think Alexandria’s as well, is that we need an ongoing grassroots movement of millions of people to pressure Congress, to pressure the corporate establishment, so that we can bring about the changes that this country desperately needs. So that’s why I have said that I will not only be commander-in-chief, I’m going to be organizer-in-chief.” (An aide to Sanders said the meeting with Obama took place in the spring of 2018.)

Sen. @BernieSanders and Rep. @AOC sat down with The Intercept’s @RyanGrim and spoke in detail about what political revolution and organizing mean to them. https://t.co/yHIDY6mjmb pic.twitter.com/5Blxwfj4d4 — The Intercept (@theintercept) October 20, 2019

After the interview, speaking before the crowd of more than 25,000, the largest for any Democrat so far in the primary campaign, Ocasio-Cortez officially endorsed the Vermont senator for president, giving a boost to a campaign that needs momentum after Sanders’s heart attack. Though Sanders has led fundraising, his main progressive rival, Warren, a Massachusetts senator, now regularly leads polls nationally and in early primary states Iowa and New Hampshire. Ocasio-Cortez’s rise is a manifestation of Sanders’s idea that by building a mass movement, working people can be lifted up. She was inspired by his campaign, volunteered for it, and then ran herself.

Take two minutes and listen to @AOC explain how a system that underpays and undervalues workers can leave them feeling worthless and how a candidate that fights for them can give them hope. #BerniesBack pic.twitter.com/ULu6rOSN46 — jordan (@JordanUhl) October 19, 2019

At the same time, she is a reminder of the limitations of what is considered possible on the inside: Sanders, after all, did not endorse Ocasio-Cortez until after her primary victory in 2018 over incumbent Joe Crowley, the longtime “king of Queens.” The debate over the fate of Obama for America, Obama’s campaign arm, goes back to 2008, when Obama adjudicated an internal dispute within his operation by mothballing the organization and folding it under the auspices of the Democratic National Committee, which itself was forbidden from pressuring Democrats to push Obama’s agenda. Some in his orbit argued that Obama’s insider approach to the presidency needed to be complemented by robust outside pressure from grassroots organizers. But Obama believed that he and his team, led by chief of staff Rahm Emanuel, would be able to work more effectively with moderates and Republicans if grassroots activists weren’t pressuring them from the outside. That turned out not to be the case. Rallies and protests are a critical element of outside pressure, but that pressure is also expressed through primary challenges to incumbents who are unenthusiastic about the president’s agenda. To that end, Sanders said that he would be looking to get more involved in primaries in the weeks and months ahead. So far, Sanders has only endorsed one challenger, Marie Newman, who is taking on Rep. Dan Lipinski in Illinois. Asked if he planned to endorse more primary challengers, Sanders said, “I think so. I think that we need to let elect a House and a Senate that is as progressive as it possibly can be, a House and a Senate that is going to work with me in fighting for health care for all, to raise the minimum wage to a living wage, to deal with the global crisis of climate change. So I will do everything I can, and have over the last number of years, to get more people involved in the political process and to elect people who are as progressive as possible.”