In California, a Republican congressman who voted to impeach Trump survives his primary.

Representative David Valadao, a Republican running in a strongly Democratic district in California’s Central Valley, will face off in November with his strongest challenger yet after primary voters gave the Republican and Democratic establishments the candidates they wanted.

Mr. Valadao, whose victory was called by The Associated Press weeks after the June 7 primary, is one of the most endangered House Republicans in the country.

He voted to impeach former President Donald J. Trump for inciting the Jan. 6 attack on the Capitol, then laid low and largely escaped Mr. Trump’s wrath. He attracted two Republican primary challengers — Chris Mathys, who ran as a pro-Trump voice, and Adam Madeiros, who campaigned as a traditional pro-agriculture conservative in the Central Valley.

Mr. Valadao’s Democratic challenger — Rudy Salas, a five-term assemblyman who is a popular fixture in the Fresno area — cleared the Democratic field the night of the primary in a district whose lines shifted in his favor, away from the outskirts of conservative Bakersfield.

In the end, Mr. Valadao’s two Republican rivals, Mr. Mathys and Mr. Madeiros, seemed to have split the anti-Valadao vote. That cleared the way for the strongest candidates to compete in one of the Democrats’ few pickup opportunities in the House in November.