David Valadao

Randy Villegas, a political scientist and school board trustee backed by progressives including Senator Bernie Sanders of Vermont, advanced in a high-profile primary in a battleground Central Valley House district, according to The Associated Press. Democrats view the district as crucial to their efforts to regain control of Congress this fall.

In the general election, Mr. Villegas will face Representative David Valadao, a vulnerable but battle-tested Republican who has survived many past attempts to oust him. Democrats are eager to test the new lines they drew in Mr. Valadao’s Bakersfield-area district last year to make it even more competitive; they are also bullish about their ability to win back Latino voters.

Mr. Villegas faced a tough Democratic opponent in Dr. Jasmeet Bains, a moderate California assemblywoman and physician who was backed by the establishment wing of the party. She is known as a “Valleycrat” — a term for a moderate Central Valley Democrat — and was considered a traditional pick whose politics were more typical for the swing district.

Mr. Villegas faced attacks from Republicans, who called him a “socialist,” and from Dr. Bains, who called him “radical Randy.” Quietly, though, a Republican super PAC spent money boosting his campaign, on the apparent assumption that he would be the easier opponent for Mr. Valadao.

Mr. Valadao, who also advanced in the top-two, all-party primary, has fended off nearly all Democratic attempts to unseat him since first entering the House in 2013. In 2018, he lost to TJ Cox, a Democrat, by just over 800 votes, but ousted Mr. Cox two years later in a similarly tight contest.