Incumbent Jim Costa (D) and Kevin Cookingham (R) advanced to the Nov. 3 general election for California’s 16th Congressional District, defeating two other candidates in the March 3 top-two primary. As of 10:00 a.m. PT on March 5, Cookingham had received 38.5% of the vote to Costa’s 37.5%, followed by Esmeralda Soria (D) with 18.4% and Kim Williams (D) with 5.6%. One Democrat and one Republican have advanced from the district’s primary in each congressional election since California’s top-two primary system went into effect in 2011.

Cookingham received the endorsement of the California Republican Party. Costa’s endorsers included Sens. Dianne Feinstein (D) and Kamala Harris (D), Gov. Gavin Newsom (D), and Rep. Adam Schiff (D). Soria was endorsed by civil rights activist Dolores Huerta, the California Labor Federation, and SEIU California. Williams received endorsements from Brand New Congress and Our Revolution.

Major race rating outlets rate the general election as Solid Democratic or Safe Democratic. The 2017 Cook Partisan Voter Index for this district was D+9, meaning that in the previous two presidential elections, this district’s results were 9 percentage points more Democratic than the national average.

All 435 House districts will be up for election on November 3, 2020, and the results will determine the partisan balance of the U.S. House in the 117th Congress. As of March 2020, Democrats have a 232-197 advantage over Republicans. If Republicans win 18 Democratic-controlled districts, they will win control of the House. If Democrats hold as many districts, they will maintain their control of the chamber.