Now the senior senator from Massachusetts, Warren was recruited by progressives to run against Hillary Clinton in the 2016 Democratic primary. She passed up the chance, helping to clear the way for her ideological ally and current presidential campaign rival Sen. Bernie Sanders to jumpstart his “political revolution.”

Asked by David Axelrod for an episode of the Axe Files airing Saturday at 7 pm ET, if she made the wrong decision, Warren didn’t blink.

“You can’t go back,” she said. “Bernie and I have been friends for a long, long time. I’m sure far before I ever thought I was going to be in the electoral end of politics. I get out there every day; Bernie gets out there every day. And so do a lot of other good people.”