California Republicans are priming for a fight in 2020, as both the state and national party have said any path to winning a majority in the U.S. House of Representatives runs through wresting back the seven California congressional districts Democrats flipped in 2018.

But the Golden State's most hard-fought congressional race may take place elsewhere, as some of Southern California's highest-profile Republicans are gearing up to battle each other in the 50th Congressional District, which historically has been one of California's most reliably red seats.

"It's too bad for the Republican Party, I think it reflects poorly upon it," incumbent Rep. Duncan Hunter, R-Alpine, said as he puffed on a vaping device. "Here you have two guys who don't live in the district that could really challenge a Democrat in districts where they live. Instead, they're choosing to go after me. And I think that's one of the problems with the party and why it's lost so many seats lately in California."

The 50th Congressional District encompasses east San Diego County and parts of western Riverside County. Hunter will face a long list of Republican challengers in 2020, including former San Diego Councilman Carl DeMaio, former U.S. Rep. Darrell Issa and state Sen. Brian Jones.

In a ballroom above slot machines and card tables at the Morongo Casino, Resort and Spa in Cabazon, Hunter, Issa and DeMaio each made the rounds, hobnobbing with potential supporters before breaking bread just a few feet from each other Saturday at the Liberty Dinner, an annual fundraiser hosted by the Riverside County Republican Party.

Both Republicans and Democrats have seen Hunter as vulnerable since August 2018, when he was indicted for wire fraud and campaign finance law violations that included allegedly spending more than $250,000 on non-campaign related expenses, including a trip to Italy and family dental bills.

The 41-year-old Marine Corps veteran had won each of his elections since 2008 by at least 25%, but in 2018 amid the indictment, Ammar Campa-Najjar, his then-29-year-old Democratic opponent, came within 3.4% of unseating him

In California, the top-two vote-getting candidates in the March 2020 primary election, regardless of party, will advance to the general election. Republicans expect Campa-Najjar, the sole Democrat in the race at this point, to advance with conservative support split among their candidates, in what they expect to be an expensive battle. Issa was the wealthiest member of Congress during his tenure from 2000-18 with an estimated net worth of $283.3 million, based on financial disclosures filed while he was in office. Republicans, including DeMaio, expect the former electronics executive to self-fund much of his campaign.

Riverside County Republican Party Chair Jonathan Ingram made sure to mention each of the candidates on stage and said the party would go through a typical endorsement process, giving each candidate fair consideration, but DeMaio said he was upset Issa was chosen to appear on stage and introduce conservative commentator Katie Holmes — a last-minute replacement former Trump administration official Sebastian Gorka, who cancelled on Tuesday.

Even after Issa's entrance into the race, DeMaio said his polling showed him as the frontrunner, due to his "track record of being a fighter for Californians who are sick of socialism."

The Reform California activist, who led last year's Prop. 6 "Gas Tax Repeal" campaign, said he was confused about Issa's motivation to return to politics after deciding not to run for reelection in the 49th Congressional District, which encompasses coastal San Diego and Orange County. Democrat Mike Levin replaced Issa after defeating former Republican Assemblywoman and Board of Equalization member Diane Harkey.

"I don't understand why someone who would quit his congressional district and cut out and run would turn around and say 'Well, now I want to run for Congress,'" DeMaio said. "It seems like he's bored or seeking a title and I don't think that's going to resonate with voters."

DeMaio acknowledged that Republican candidates challenging a GOP incumbent in a hard fought primary battle would be costly and potentially divert resources that could be used in battleground districts. But he said he couldn't control the actions of other candidates and blamed Issa.

After not seeking reelection to his 49th District Congressional Seat in 2018, Issa said his motivations for running for Congress again had to do with the attacks on the president from his former Democrat colleagues, specifically naming Rep. Adam Schiff, D-Calif., Rep. Jerry Nadler, D-N.Y., and Rep. Bob Menendez, D-N.J.

"I'm watching these attacks on the president. These are people I know very well and I'm watching them prepare to impeach the president still looking for what to do it about," he said.

If elected, Issa said he would revisit many of the issues he worked on in Congress during his first tenure, specifically mentioning homelesness and border security.

He's fielded attacks from both Hunter and Campa-Najjar about his choice not to seek reelection to his former seat and not living in the 50th District, but Issa said he understands the area well because he represented parts of the district from 2000 up to 2012, when the state redrew congressional districts.

"I've represented a third of this district for longer than [Campa-Najjar] has been old enough to vote," he said. "When people look at the 2.2 miles between my house and the district or, by the way, the 2.4 miles inside the district where my other house is. I could move my residency from one house I own to the other house I own, but the reality is that Fallbook, Valley Center, Temecula: these are all areas I've represented for decades."

Ingram, the county party chair, said he was satisfied Issa, DeMaio and Hunter all made it out to the Morongo Casino in Cabazon for the party's annual dinner fundraiser. As party chair, he said he wanted to support candidates who understood the issues facing Riverside County. He said he encouraged spirited debate but wanted to make sure Republicans weren't "feeding on (their) own."

"You want Riverside County?" he said, referring to Republican and Democratic candidates. "You're going to have to come take it."

Sam Metz covers politics. Reach him at samuel.metz@desertsun.com or on Twitter @metzsam.