Incumbents Ken Calvert (R) and Young Kim (R) are running in the general election to represent California's 40th Congressional District on Nov. 3. They defeated six other candidates to win the top-two primary on June 2.

Heading into the election, Calvert represents California's 41st Congressional District, and Kim represents the 40th District. The two incumbents were drawn into the same district as a result of Proposition 50, a redistricting amendment voters approved in November 2025. According to ABC7's Josh Haskell, Calvert represents 51% of the new district and Kim represents 35% of the new district. In the primary, Calvert received 35% of the vote and Kim 21%.

With an intraparty election, negative advertisements have been central to each campaign. Both candidates have released advertisements claiming the other is liberal or not enough of a supporter of President Donald Trump (R). One Calvert advertisement claims Kim is a RINO (Republican in Name Only) who threatened to "whip [Trump's] butt." Kim released an advertisement showing headlines from the 1990's coverage of Calvert being in a car with a prostitute. The advertisement says, "Screwing us, servicing himself, sabotaging Trump. Ken Calvert, what a sleazebag."

As of July 9, notable endorsements for Calvert included Republican gubernatorial candidate Steve Hilton, the California Republican Assembly, and the California Congress of Republicans. Notable endorsements for Kim included U.S. Rep. James Gallagher (R-Calif.), state Senate Minority Leader Brian Jones (R), and Americans for Prosperity Action.

Calvert was first elected to Congress in 1992. He received his associate's degree from Chaffey College and his bachelor's degree from San Diego State University. Before his election to Congress, Calvert was a small business owner in the restaurant and real estate industries.

Calvert is running on his record. His campaign website says, "Ken’s legislative work has received top ratings from the Americans for Tax Reform, U.S. Chamber of Commerce, National Federation of Independent Businesses, National Association of Manufacturers, and the 60 Plus Association." He highlighted his legislation creating the E-Verify system to verify employees' legal status, securing federal funding for transportation and environmental projects, and constituent services.

Kim was first elected to Congress in 2020. She received her bachelor's degree from the University of Southern California. She worked as a business owner, financial analyst, and staff for then-U.S. Rep. Ed Royce (R). She represented District 65 in the California State Assembly from 2014 to 2016.

Kim is running on her record. Her campaign website says, "In Congress, I continue to fight every day to ensure President Trump has allies to undo the disastrous Joe Biden-Nancy Pelosi agenda that caused skyrocketing prices, rising crime, an open border, and a political class that serves the swamp instead of fighting for working families."

The outcome of this race will affect the partisan balance of the U.S. House of Representatives in the 120th Congress. All 435 U.S. House districts are up for election.

Currently, Republicans have a 219-212 majority with four vacancies in the chamber. To read more about the U.S. House elections taking place this year, click here.