The nation’s last outstanding congressional race was called late Tuesday, with voters in California’s Central Valley handing Democrats one more seat in the House.

Democrat Adam Gray won his rematch against freshman GOP Rep. John Duarte in California’s 13th Congressional District, eking out one of the closest wins of this election cycle. The Associated Press called the race in favor of Mr. Gray, who toppled Mr. Duarte by fewer than 200 votes.

Mr. Gray’s win brings the total flips in the Golden State to three seats.

“The final results confirm this district is ready for independent and accountable leadership that always puts the Valley’s people ahead of partisan politics,” Mr. Gray posted on X.

The contest came to a close almost a month after Election Day, and was the last race that Republicans and Democrats were watching to determine exactly what their majority and minority would look like.

The outcome gives House Republicans a 220-seat majority, with Democrats increasing their total to 215 seats in the lower chamber. Come early next year, that majority will be even closer when President-elect Donald Trump’s Cabinet appointments from the House leave, effectively giving Republicans a zero-seat majority at 217 to 215.

Mr. Duarte won in a similar fashion two years ago, when he edged out Mr. Gray by nearly 600 votes to head to Washington in a contest that was not decided until three weeks after the election ended.

He told local newspaper the Turlock Journal that he called Mr. Gray to concede Tuesday.

“I’m a citizen legislator, and I didn’t plan on being in Congress forever,” Mr. Duarte said.

• Alex Miller can be reached at amiller@washingtontimes.com.