One of California’s most influential power brokers pleaded guilty to three felonies on Thursday in a corruption case that has reverberated through the State Capitol and spurred attacks on a Democratic front-runner in the volatile race for governor.

That powerful figure, Dana Williamson, appeared in federal court in Sacramento, where she accepted reduced charges and pleaded guilty to lying to the F.B.I., filing a false tax return and conspiracy to commit bank fraud and wire fraud...

While her case prompted speculation in November about whether her acts were tied to her work in Mr. Newsom’s office, there has been greater scrutiny this month on her connections to Mr. Becerra because of his unexpected surge in the governor’s race.

The plea deal, as laid out in court filings, dramatically reduced the number of charges against Ms. Williamson. In exchange, she would pay more than $500,000 in restitution, the agreement says, and could face time in prison, to be determined at a sentencing hearing later this year.

The alleged scheme saw Williamson siphon campaign funds from Becerra’s state campaign account to pad the salary of his chief of staff, Sean McCluskie. McCluskie and another alleged co-conspirator, lobbyist Greg Campbell, accepted plea deals around the time Williamson was indicted and are scheduled for sentencing on June 4.

“As part of an investigation that began in 2022, Williamson joins the two others who were charged in the ‘Conduit Scheme’ conspiracy in pleading guilty,” said U.S. Attorney Eric Grant in a statement. “These conspirators, three of whom are former public officials, shockingly looted campaign funds for personal benefit. Our office and our law enforcement partners will continue working to protect the integrity of the electoral process and ensure that those who scorn the law are held accountable.”

Plea deal documents filed Thursday morning note that Williamson and her co-conspirators made “false statements” to Becerra about the purpose of the funds being siphoned from his account.