Democrat Gil Cisneros extended his lead over Republican Young Kim on Friday in California’s 39th Congressional District, depressing the GOP’s prospects for retaining its last House seat in Orange County.

Updated vote tallies released by election officials in Los Angeles and Orange counties showed Kim trailing Cisneros by 3,020 votes.

On election night, Kim finished almost 3,900 votes ahead, but Cisneros has been gaining ground ever since.

The Nov. 6 election results have been dismal for Republicans: They have lost five House seats in California.


Most alarming for the GOP is the growing prospect that for the first time since the Great Depression, there will be no Republican in Congress representing Orange County, a longtime party stronghold.

Young Kim, a Republican candidate, has fallen behind in the race to succeed Rep. Ed Royce (R-Fullerton). (Genaro Molina / Los Angeles Times)

Democrats have ousted Republican incumbents Dana Rohrabacher in Orange County’s 48th Congressional District on the coast and Mimi Walters in the adjacent 45th that covers Irvine and surrounding areas.

Democrats also have unseated Republican Reps. Steve Knight of Palmdale in the 25th District and Jeff Denham of Turlock in the Central Valley’s 10th. Voters also picked a Democrat, Mike Levin, to replace Rep. Darrell Issa (R-Vista) in the 49th, which includes Carlsbad, Oceanside and San Clemente.


Cisneros and Kim are vying to replace retiring Republican Rep. Ed Royce of Fullerton in the 39th District, which contains portions of Orange, Los Angeles and San Bernardino counties.

In another Central Valley district, the 21st, the Associated Press has projected GOP incumbent David Valadao as the winner. But in the continuing vote count in Fresno, Kern, Tulare and Kings counties, Democrat TJ Cox has narrowed Valadao’s lead to just 2,086 votes, down from 4,839 on election night.

If Cox and Cisneros win, Democrats will have captured all seven of the Republican-held districts in California that then-candidate Donald Trump lost to Hillary Clinton in 2016.

With the growing dominance of mail ballots in California, roughly 40% of the votes are counted in the weeks after election day, and they almost always skew Democratic.


That’s not due to fraud, as some partisans allege, but the fact that older, more conservative voters tend to vote early, and younger, more left-leaning voters cast their ballots closer to election day, meaning they are tabulated later.

michael.finnegan@latimes.com

Twitter: @finneganLAT

maya.sweedler@latimes.com


Twitter: @mayasweedler

UPDATES:

6:55 p.m.: This article was updated with the latest vote margin in the 21st Congressional District.

This article was originally published at 6:15 p.m.