File photo of California State Senator Leland Yee speaks about state budget impasse in San Francisco Thomson Reuters SAN FRANCISCO/SACRAMENTO (Reuters) - A prominent California lawmaker was arrested on Wednesday in an FBI sweep that netted 26 people, a high-profile case that could affect statewide elections and brings to three the number of Democratic state senators who face criminal charges this year.

Senator Leland Yee, a former San Francisco supervisor and one-time mayoral candidate, was criminally charged in federal court in San Francisco with two felony counts of conspiring to import and traffic in firearms, and six corruption counts.

Yee was released on $500,000 bond and declined to comment on the case.

A criminal complaint posted online by the U.S. Attorney office for the Northern District of California alleges that Yee did favors for an undercover FBI agent in exchange for campaign contributions. The complaint alleges that Yee also offered to facilitate a meeting between the undercover agent and an arms dealer, and discussed the types of weapons that the undercover agent might need.

Yee's arrest deals a body blow to California Democrats, whose two-thirds majority in the state Senate was eroded when Senator Ron Calderon, indicted on corruption charges, and State Senator Rod Wright, found guilty of voter fraud, took paid leaves of absence earlier this year.

Democrats control large majorities in both houses of the state legislature and all statewide offices, but having a third senator under a cloud could seriously undermine the party's ability to push key projects in an election year.

"If I were advising the Democrats at this time I would say, 'Pull back everything big until you get the supermajority back,'" said Sherry Bebitch Jeffe, a political analyst at the University of Southern California. "I wouldn't get into immigration, I would not get into water or anything they would need to negotiate with the Republicans."

Republican lawmakers, who hardly have had any say in state government since the Democrats won a so-called super-majority with two-thirds of the seats in the legislature, had harsh words not only for Yee but for the Democratic leadership that has refused to oust Wright and Calderon, putting them instead on paid leaves of absence.

"It's a shame that some people misuse the privilege to serve the people that has been entrusted to them," said state senator Andy Vidak, who has led the Republican charge to oust Wright and Calderon.

MORE ARRESTS

Federal authorities also arrested Raymond "Shrimp Boy" Chow, alleged to be the head of a Chinese organized crime syndicate, and two dozen other people, Melinda Haag, the U.S. Attorney for the Northern District of California, said in statement late Wednesday.

A political consultant who worked with Yee, Keith Jackson, was also arrested and faces numerous charges including firearms trafficking, involvement in a murder-for-hire case and corruption, according to the complaint and press release.

Yee, a San Francisco Democrat, is running for Secretary of State and had been considered a strong candidate in a big field of both Democrats and Republicans. It is not yet clear how his arrest will affect that race.

In their complaint, prosecutors allege that Yee, trying to raise money to retire debt from his failed 2011 mayoral campaign, did favors for an undercover FBI agent who said he needed a phone call made to the California Department of Public Health in order to be favorably considered for a contract.

The complaint also alleged that after an undercover agent told Jackson that he needed to purchase a large number of weapons, Jackson said Yee could facilitate a meeting with an arms dealer in exchange for a contribution.

"During a meeting with the undercover agent, Yee and Jackson allegedly discussed details of the specific types of weapons the undercover agent was interested in buying and importing," the U.S. Attorney's office said.

Senate Democratic leader Darrell Steinberg hastily canceled a planned news conference on Wednesday after learning of Yee's arrest in a phone call early Wednesday morning, a spokesman said.

Throughout the early part of the day, the hallway outside of Yee's office at the state capitol in Sacramento was crowded with reporters and other onlookers hoping for a glimpse of FBI agents working behind a closed door. Agents began searching Yee's office early Wednesday morning, the FBI said.

Lee, a child psychologist with a PhD., emigrated to San Francisco from China at the age of 3.

(Reporting by Dan Levine in San Francisco and Sharon Bernstein in Sacramento; Editing by Alex Dobuzinskis and Ken Wills)