After last year’s midterm drubbing, which cost Republicans seven California congressional seats, GOP leaders are going all out to try to show that those Democratic wins were one-off aberrations that won’t be repeated in 2020.

“We’re very confident we can get those seats back,” said Torunn Sinclair, a spokeswoman for the Republican National Congressional Committee. “These are all seats we held in 2016” and for years before that.

But Republicans don’t hold them now, and that’s embarrassing for the party. Not only did those flipped seats help the Democrats take control of the House, but they also came from some of the state’s best-known GOP strongholds.

Four of those new Democratic seats are in Orange County, which, for the first time since the 1930s, doesn’t have a single Republican in Congress. Two others are in the Central Valley, and the seventh is in the northern edges of Los Angeles County.

The Republican Party is recruiting some big-name candidates they hope can take back those seats.

“There are a lot of folks who want to run against the socialist Democrats who were just elected,” said Sinclair, rolling out the type of attack Republicans in California and across the nation will take against liberal — and not-so-liberal — Democrats.

While Sinclair insisted that the national party won’t be putting its “thumb on the scale” to favor any particular GOP primary candidate, local Republicans have no such qualms.

“We want to see who the strongest candidates are and get behind them early,” said Fred Whitaker, head of the Republican Party of Orange County. “We want our candidates to get out early so they don’t have primary wars.”

Although the filing deadline for California’s March 2020 primary isn’t until Dec. 6, GOP leaders in Orange County already have anointed two congressional candidates and are ready to get behind a third.

In the 39th district, Republican businesswoman Young Kim is lining up for a rematch against Democratic Rep. Gil Cisneros of Yorba Linda (Orange County), who beat her by 7,600 votes for the open seat last year. Farther south in the 48th District, Orange County Supervisor Michelle Steel is the GOP establishment’s choice to go against Democratic Rep. Harley Rouda of Laguna Beach.

Kim was instantly endorsed by House GOP leader Kevin McCarthy of Bakersfield, who called her “one of the top recruits in the country for House Republicans.”

The conservative Orange County Lincoln Club, which is made up of prominent GOP donors, has already endorsed both Kim and Steel, Whitaker said.

In the 49th District, which spreads across Orange and San Diego counties, San Juan Capistrano Mayor Brian Maryott, who finished eighth in the 2018 primary, is the likely GOP choice to challenge Democratic Rep. Mike Levin, Whitaker said. The Orange and San Diego county GOP parties are expected to endorse him by June.

The only Orange County question mark is in the 45th District, where there are five Republicans running to unseat newly elected Democratic Rep. Katie Porter.

“We’ll interview them and see who comes out of the June 30 (campaign finance) reports,” Whitaker said. “They need to show the party and the donors what they can do.”

The GOP opposition lineup is far less settled elsewhere in the state. In the Central Valley’s 21st district, for example, no Republican has filed to challenge Democratic Rep. TJ Cox, even though he beat GOP Rep. David Valadao by fewer than 900 votes in November.

“It’s still really early,” Sinclair said. “There’s still lots of time” for a Republican to get in.

The lineup for the 10th District became a little clearer recently when Republican Jeff Denham, who lost in November to Democratic Rep. Josh Harder of Turlock (Stanislaus County), joined a Washington, D.C., lobbying firm and said he had no plans to run again.

That leaves five Republicans in the 2020 mix, including Ted Howze, who finished third in the June 2018 primary, and Marla Sousa Livengood, who lost last year to Rep. Jerry McNerney, D-Stockton, in the neighboring Ninth District. Bob Elliott, a San Joaquin County supervisor, jumped into the race last week, abandoning his previously announced plan to run for the state Senate.

In the 25th District, first-term Rep. Katie Hill, D-Santa Clarita (Los Angeles County), has four GOP challengers so far.

California Democrats already are lining up against their likely challengers, tying them to President Trump, who remains unpopular even in Republican-leaning parts of the state.

Rouda’s team has billed Steel as “a Trump appointee and a career politician,” because she was named this year to the President’s Advisory Commission on Asian Americans and Pacific Islanders.

Rouda’s people argued that “this is not the time to elect someone who will stand with Donald Trump as he pretends climate change isn’t real, undermines our health care and pounds middle-class Orange County residents with higher taxes.”

As for Kim, a fundraising letter from Cisneros called her “an integral piece of the Republicans’ strategy to retake the House,” saying that “she has made it clear from day one that her allegiance is with Trump.”

Little has changed since November’s election, Democrats argue, and with Trump at the top of the 2020 ballot, they believe their re-election prospects look good.

State Republicans believe that the likelihood of a hard-fought presidential race is actually good news for them, because that battle won’t be in California, said Whitaker, the Orange County GOP leader.

“The big difference in 2018 was the amount of money the Democrats spent,” he said. “They had to take control of the House, and that’s where the money went.”

But for Democrats, 2020 is going to be all about beating Trump, Whitaker said, and “that money will be spent in the Midwest to challenge the president.”

Incumbency can bring its own problems for the first-term Democrats, Sinclair suggested, especially if the Republicans can recruit good candidates to challenge them.

“This time they’ll have to run on their records,” she said. “Not on their rhetoric.”

John Wildermuth is a San Francisco Chronicle staff writer. Email: jwildermuth@sfchronicle.com Twitter: @jfwildermuth