Rep. Gary Condit on Tuesday resoundingly lost his uphill bid to hold on to his Central Valley congressional seat, his successful political career ended by his relationship with missing intern Chandra Levy.

Condit's defeat, at the hands of a onetime friend and protege, Assemblyman Dennis Cardoza, marked the end of a 30-year political career. Cardoza was one of several Democrats who challenged Condit for a seat that, until Levy disappeared last spring, was considered a sure bet for the incumbent. Instead, Condit became one of the few entrenched incumbents to lose a primary contest.

Although police have said they do not consider him a suspect in the case, questions about the married congressman's relationship with the 24-year-old intern derailed his career and brought the unwelcome glare of the national spotlight to his conservative agricultural district. For most of Tuesday, Condit avoided reporters and reportedly stayed at home to await word of his fate.

"Today the people of the Central Valley stood up for their values, the values that are central to their lives," Cardoza said in a victory speech shortly after 10:30 p.m.

About the same time, Condit emerged from his house in Ceres, dressed in a purple fleece sweatshirt and blue jeans. The congressman avoided conceding, but thanked the voters of the 18th District and the people who worked on his re-election bid.

"I appreciate their support, their love," he said. "I will never forget that."

About 15 minutes after his statement, the sprinklers went on, dousing a gaggle of television reporters and cameramen staked out in front of his house.

Condit kept a low profile on the day of his reckoning, ducking the media as he toured his district in a last-ditch effort to win support. Dogged by his relationship with Levy, he faced the toughest battle of his three decades in politics. A conservative Democrat who long espoused family values, the seven-term congressman had seemed assured of yet another easy re-election victory a year ago.

But things changed when Modesto native Levy vanished from Washington, D.C., in May, just as she was about to return to USC to accept her master's degree. Relatives of Levy, who had completed a federal internship as part of her studies, said she had had an affair with the 53-year-old Condit, who has two grown children.

Condit has repeatedly refused to discuss details of his relationship with Levy except to acknowledge that they were close. For several months, until Sept. 11, he was the subject of intensive media coverage and became grist of late-night television talk and comedy shows.

As Condit's once-loyal constituents showed signs of anger with him, party leaders abandoned the congressman, who had once been a trusted confidant to Gov. Gray Davis. State legislators even redrew his district to make it harder for him to win the Democratic nomination. Republicans indicated that they would probably target the strongly Democratic district if Condit survived the primary. Four Republicans, including state Sen. Dick Monteith of Modesto, filed for the race in a district where Democrats have a 52 percent to 35 percent registration edge.

Cardoza outdistanced Condit and the other Democratic candidates in fund-raising, endorsements and public opinion polls. But Condit fought back, stumping with his family through the district and using his own money to help finance his campaign. Cardoza will face Monteith in November.

On Tuesday, residents in Modesto waited for the election results that many hoped would take the Central Valley town out of the national spotlight.

"I think he's a liar, and he abused his power," said Terri Richey, 40, as she shopped at a florist's a few doors down from Condit's office. She said she voted for one of his challengers.

But others were supportive.

"Well, you know, he's done a lot for this area," said Shannon Gonzalez, 29, a Republican. "I tend to be one of those people who likes to judge people on what they've done and try to keep their personal life out of it."

Los Angeles Times staff writers Claire Luna, Richard Marosi, Doug Smith and Kenneth Weiss contributed to this report.