During her introduction of Senator Bernie Sanders at a campaign event in Cedar County, Iowa on Monday, Oscar-winning actress Susan Sarandon took what appeared to be a swipe at his primary progressive competition for the 2020 presidential nomination.

“When people know and when they hear the senator’s policies, when they see his track record, when they know how authentic he is and how he has been fighting for these issues for so long, he is the only one who has that reputation,” Sarandon said from the stage. “He is not someone who used to be a Republican. He is not someone who used to take money—or still takes money—from Wall Street. He is the real deal.”

The line about “someone who used to be a Republican” caught the ear of Politico’s 2020 campaign reporter Holly Otterbein, who pointed out on Twitter that while Sarandon didn’t “name names,” of the other major candidates in the race it is Sen. Elizabeth Warren (D-MA) who was a registered Republican until the mid-1990s.

Speaking to ABC News anchor George Stephanopoulos in 2014, Warren explained that she was “with the GOP for a while” because she “really thought that it was a party that was principled in its conservative approach to economics and to markets.”

“And I feel like the GOP party just left that,” Warren added. “They moved to a party that said, ‘No, it’s not about a level playing field. It’s now about a field that’s gotten tilted.’ And they really stood up for the big financial institutions when the big financial institutions are just hammering middle class American families.”

Warren has said that the only Republican presidential nominee she voted for in her lifetime was Gerald Ford in 1976. The Daily Beast reached out to the Sanders campaign to ask whether the candidate believes Warren’s past as a registered Republican is fair game.

Earlier in her introductory speech on Monday, Sarandon called 2020 the “make it or break it election” and accused the “mainstream media” of “either suppressing or corrupting or misrepresenting” information about Sanders’ candidacy.

Sarandon was an outspoken supporter and surrogate for Sanders during the 2016 primary as well and famously refused to shift her support to Hillary Clinton during the general election, casting her vote for Green Party nominee Jill Stein in her native New York.

Months before the 2016 election, Sarandon went on MSNBC’s All In with Chris Hayes and suggested that Clinton would be a more “dangerous” president than Trump, declaring, “some people feel that Donald Trump will bring the revolution immediately if he gets in, things will really explode.”