LOS ANGELES – It's a showdown that — regardless of the outcome in the June 2 primary election — probably won't have Republicans in a celebratory mood.

The battle for the 40th Congressional District representing a swath of inland Orange County and portions of San Bernardino and Riverside counties is happening in one of Southern California's only remaining solidly red districts. But that doesn't provide much solace, experts say.

The shuffling of districts following the passage of Proposition 50, which gave Democrats in Sacramento the authority to redraw the state's congressional districts in favor of Democratic candidates, is pitting two current members of Congress — Young Kim, R-Anaheim Hills, and Ken Calvert, R-Corona, — against each other in a bid to keep their seat.

The two are also fending off challenges from a host of Democrats and an independent candidate who says she hopes to win votes from those disenchanted by deeply partisan politics felt across the country.

But even if a Republican keeps the seat, California's Republican congressional delegation is still down by another member.

"It was all part of the Prop. 50 effort," said Jon Fleischman, a conservative strategist. "Not only did they reduce the number of seats that Republicans have, they got to shove a couple of incumbents into one seat and eat popcorn and watch the food fight."

And the gloves are already off.

Kim launched a $3.7-million ad blitz last month with a video boasting her support of President Donald Trump, saying that she's a "trusted Trump conservative."

Calvert's campaign responded in an attack ad that referred to Kim as a RINO, or Republican in name only, a pejorative term frequently used by Trump and others in the GOP to describe conservatives perceived as being disloyal to the party and a "Trump traitor."

The television advertisement, which began airing last month, called attention to Kim co-sponsoring legislation with other Republicans to censure Trump in 2022 after the Jan. 6, 2021, attack on the U.S. Capitol. Democrats widely criticized the move as a slap on the wrist.

"I believe censuring the president after his actions helps hold him accountable and could garner wide bipartisan support, allowing the House to remain united during some of our nation's darkest days," Kim said at the time.

The nonpartisan Cook Political Report lists the 40th District, which extends from Villa Park south to Mission Viejo in Orange County and into Corona, Murrieta and Menifee in the Inland Empire, as being solidly Republican.

It's the only House seat that was competitive under the old congressional district map that is now fairly safe for the GOP. Trump would have won the district by 12 points in 2024.

As the two incumbents trade jabs, Democrats Esther Kim Varet, an art gallery owner; Lisa Ramirez, an immigration attorney; Joe Kerr, a retired fire captain; and Claude Keissieh, an electrical engineer; are hoping to garner enough support among the progressives in the district to advance to the November election.

Nina Linh, who entered the race early on as a Democrat but has since identified as an independent, is hoping to make inroads with voters disenchanted by both parties.

"When I look at our political climate, I have never in my adult life witnessed or experienced anything so polarized," she said in a recent interview. "And people, including myself, are just exhausted from this back-and-forth rhetoric for over a decade that has gotten us into a culture of just hyper-divisiveness and extreme partisanship that is prioritized over what everyday people are concerned about."

Dan Schnur, who teaches political communications at USC, UC Berkeley and Pepperdine, called the race in the 40th District a "classic matchup between the two Republican parties — the pro-Trump party and the pre-Trump party."

Kim, who in 2020 was one of the first Korean American women elected to Congress, does vote to advance Trump policies, but her biography is more consistent with an earlier era of conservatism. Calvert, the longest-serving Republican in California's congressional delegation, has much more aggressively positioned himself in line with Trump, Schnur said.

The district is representative in a lot of ways of the two types of Republicans that make up much of the party's base — MAGA supporters and traditional Republicans who have either come to accept Trump or quietly resent him.

"Not only is this district reflective of the challenge that the party is facing around the country this year, it could be an early precursor of what Republicans will face in the 2028 presidential primary," Schnur said.

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