The news of Rep. Alexandria Ocasio-Cortez’s planned endorsement of Sen. Bernie Sanders came as a shock Tuesday night, capping his comeback performance at the fourth Democratic debate. Many expected she would not endorse at all, or at least not before the New York primary. AOC, some speculated, wouldn’t risk alienating mainstream Democrats who projected their own politics on a young, telegenic woman of color. They were wrong.

Even before his health scare, the pundit class had written off the Sanders campaign. Warren has recently overtaken Biden in most national polls, and the liberal commentariat has come to see her as both the front-runner and the Left’s standard-bearer. With four months to go before a single vote is cast, Sanders was written out of 2020 discussions.

Then came AOC joined by Ilhan Omar and Rashida Tlaib — at a moment that couldn’t have been more precarious. (We now know that, according to Politico, AOC informed Sanders of her decision to join his campaign as he lay in a hospital bed in Nevada recovering from a heart procedure.) Liberal pundits, already equating Warren’s professional-class reformism with Sanders’s working-class radicalism, would have been more than happy to keep promoting AOC, Omar, and Tlaib as political renegades against the status quo even if they had chosen to stay safely on the sidelines. The three representatives could have had the best of both worlds all without taking an enormous political risk. Instead, they took the risk.