White House candidate Michael Bloomberg has hired a senior staffer from Sen. Kamala Harris’s (D-CA) flailing campaign, Politico first reported on Wednesday.

A spokesperson for Bloomberg’s recently-launched campaign confirmed that Kelly Mehlenbacher will serve as deputy chief operating officer. Mehlenbacher worked as an operations specialist for Harris’s campaign. She’s a longtime Democrat operative, who also worked on Hillary Clinton’s failed White House bid in 2016.

The development comes after the California senator, dogged by falling poll numbers and slumping fundraising figures, laid off staffers at her Baltimore headquarters and in the early primary state of New Hampshire.

Bloomberg, a billionaire and former New York City mayor, formally launched his presidential campaign on Sunday and has already begun a $30 million television advertising campaign, the biggest-ever purchase of its kind for a primary election contest.