SAN DIEGO (AP) —

With Republicans fighting among themselves, the only Democrat easily advanced to a runoff in the race to fill the California U.S. House seat vacated by convicted GOP Rep. Duncan Hunter. Now comes the hard part for Ammar Campa-Najjar.

The 31-year-old former Obama administration public affairs official is trying to flip Southern California's most Republican congressional district, where the GOP holds an 11-point advantage among registered voters.

His likely opponent in November is former nine-term GOP U.S. Rep. Darrell Issa, one of the nation's wealthiest lawmakers during his time in Congress.

Campa-Najjar had about 34% of 123,000 votes tabulated Wednesday in the 50th District that is mainly in San Diego County. Issa was second with about 25% and San Diego radio host Carl DeMaio, a Republican who sparred often with Issa during the primary, was third with 21%. There still were tens of thousands of ballots to count.

Campa-Najjar, a political newcomer in 2018, fired up the Democratic base as the first Latino Arab American to run for Congress. He came within 3 percentage points of defeating Hunter, who was under indictment on corruption charges during the race and later pleaded guilty and resigned.

Now, Campa-Najjar is tacking to the middle to try to attract more independents and Republicans who want someone other than a strident supporter of President Donald Trump like Issa.

Among other things, Campa-Najjar has said he's not sure if he would have voted to impeach Trump and is touting his gun ownership, an important issue in a largely rural district with many military veterans.

He has vowed to work on increasing affordable housing, cutting middle-class taxes, supporting veterans and protecting Medicare and Social Security. In 2018, he ran on a platform that focused on free community college and an opt-in version of Medicare for all.

Campa-Najjar wasted no time Tuesday night addressing Republican voters after early voting results showed him leading the pack of candidates trying to keep the seat in the hands of the GOP, which holds just six of California's 53 House seats.

“You can vote for Trump and for me because it’s about putting country over party,” Campa-Najjar said while surrounded by supporters.

He joined the Obama administration in 2013, selecting constituent letters for President Barack Obama to read. He later worked in public affairs in the Labor Department and the U.S. Hispanic Chamber of Commerce. After leaving government, he started ACN Strategies, a marketing company.

During this election, some progressives criticized him for steering too far away from his Democratic roots. The San Diego Progressive Democratic Club considered rescinding its endorsement before the primary.

But political analysts say it's his only path forward in one of California's last conservative bastions, where Issa, a multimillionaire businessman, spent more than $2.7 million during the primary. Campa-Najjar spent $1.2 million.

“It’s a sensible strategy for a district like this," said Jack Pitney, a political science professor at Claremont McKenna College, adding that there's little risk of losing Democrats given “the anti-Trump sentiment is going to run very high." To win, Campa-Najjar needs independents and moderate Republicans.

Issa, 66, rose to national prominence as chairman of the powerful House Oversight and Government Reform Committee. From that perch, he was a thorn to Obama, issuing repeated subpoenas of administration officials and holding hearings on issues such as the attack on U.S. facilities in Benghazi, Libya, and investigating the Internal Revenue Service’s treatment of conservative groups.

After narrowly winning reelection in 2016, Issa decided not to run again two years later in the seaside 49th District where Democrats had been gaining ground. He still lives there as he runs to represent the neighboring 50th.

Issa has yet to publicly comment on the primary results. In a statement Tuesday night, his campaign said, “The results aren’t complete yet but we believe what’s come in so far shows voters realize Darrell Issa is the conservative in the race who will help President Trump enact his agenda.”

Campa-Najjar highlighted the distinctions between himself and Issa. Campa-Najjar grew up and lives in the 50th, a region of suburbs and farm towns east of San Diego that includes the city of Temecula in Riverside County.

“Don’t be fooled, this election is not a partisan showdown between the left and the right, but a clash between an East County outsider and Washington insider, a product of the working class versus a member of the political class, old versus new," Campa-Najjar said in a statement. “Voters deserve an election where the focus is on them for a change, instead of negative attacks or desperate maneuvers from career politicians."

Issa and DeMaio share Trump's views on gun rights and stricter immigration enforcement but had an especially fierce primary fight. Calling each other liars, they tried to make voters believe the other is not truly in step with the president, who did not endorse either candidate.

During the primary, Issa was criticized for campaign ads that noted the sexual orientation of DeMaio, who is gay.

Issa so far has not been as hard on Campa-Najjar, who was attacked repeatedly by Hunter in 2018. Hunter ran ads suggesting Campa-Najjar was an Islamic terrorist because his paternal grandfather helped plan the attack on Israeli athletes at the 1972 Olympic Games in Munich.

Campa-Najjar never met his grandfather, who was killed in 1973 by the Israeli military, and he has repeatedly denounced his actions. Campa-Najjar is a Christian raised by a Catholic Mexican American mother who divorced his Palestinian father when he was a child.

The ad by Hunter was assailed as racist.

San Diego political analyst Carl Luna said Issa, who is Arab American, may not bring up Campa-Najjar's complex family history.

“Since Issa has a comfortable voting majority in the district, he may temper his campaign," he said.

Hunter resigned in January after pleading guilty to misuse of campaign funds. The former Marine held the seat for 11 years, taking it over from his father, Duncan L. Hunter Sr., who represented the area for 28 years.

Hunter is scheduled to be sentenced March 17.