LAGUNA NIGUEL, Calif. (AP) " Thirty years ago, California U.S. Rep. Dana Rohrabacher campaigned for Congress as the face of the Reagan revolution.

The conservative campus activist and surfer known for his libertarian streak had worked for Ronald Reagan's presidential campaigns and later as a White House speechwriter. His posters displayed his image with the face of the 40th president.

The 71-year-old still surfs, but the days of unabashedly proclaiming his Republican bona fides are gone.

Locked in a tight race in a Southern California district much changed from the one that first sent him to Washington, even a Republican Party mailer makes no mention of Rohrabacher's party ties but refers to him as a "political maverick."

"I'm taking on both parties," Rohrabacher proclaims in a campaign ad arguing for protecting health care for people with pre-existing conditions. At his side is his teenage daughter, who was diagnosed with leukemia when she was 8.

It doesn't mention that Rohrabacher voted repeatedly to repeal former President Barack Obama's health care law and its safeguards for pre-existing conditions. His campaign said those votes were largely symbolic and intended to highlight problems with the law.

Through 15 consecutive elections, Rohrabacher never had much of a struggle in a district with devoted Republican voters that includes the wealthy enclaves of Newport Beach and Laguna Beach.

But a wave of new and more diverse residents and divisions over President Donald Trump and the #MeToo movement against sexual misconduct have him in a toss-up race against Democrat Harley Rouda that could become a tipping point in the fight to control Congress.

Democrats need to flip 23 seats nationwide, and Rohrabacher's district is one of four in Orange County that the party hopes to claim.

His re-election fight is testing whether a congressman closely aligned with Trump can be re-elected in a district that has grown less white, more Democratic and went to Hillary Clinton in the 2016 presidential contest.

Rohrabacher needs a strong Republican turnout while attracting middle-ground voters. His challenges include making his Reagan-era conservative views appealing to newer voters, while holding college-educated Republican women, who polls suggest are turned off by Trump and the nomination hearing for Supreme Court Justice Brett Kavanaugh.

"You know who I am," Rohrabacher said, looking into the camera during a recent televised debate with Rouda. "You can trust me."

California is a strongly Democratic state, but Rohrabacher's district falls entirely within Orange County, a place of marinas and country clubs known as a foundation block in the modern conservative movement. Reagan likened it to a Republican heaven, and its miles of suburban sprawl have been synonymous with Republican political strength for decades.

Republicans hold a 10-point registration edge in the district, which Rohrabacher won by 17 points two years ago.

While Trump's 2016 victory exposed Democratic vulnerabilities across America's Rust Belt, it reinforced how reliably Democratic California has become. Trump lost by more than 4 million votes, a shockingly high figure that accounted for Clinton's victory in the national vote count.

Republicans have been losing ground in California for years, where Democrats hold every statewide office, both chambers of the Legislature and a 3.7 million edge in voter registrations. The last Republican presidential candidate to carry the state was George H.W. Bush in 1988, the same year Rohrabacher won his first term.

Rohrabacher is a climate change skeptic, an outspoken opponent of illegal immigration and Russia's leading defender on Capitol Hill. His name has come up in the investigation into Russian meddling in the 2016 presidential election, though no criminal wrongdoing has been alleged and he denies any impropriety.

The congressman has never been a cookie-cutter Republican: He supports legalized marijuana and voted against the Republican tax plan, saying it would hurt his district.

In the June primary, Rohrabacher finished first in a crowded field but pulled in just 30 percent of the votes.

Mary Kyle, a technical writer from Huntington Beach, is the kind of voter Rohrabacher needs to be concerned about. Though registered as a Democrat, she routinely splits her ticket and has voted for Rohrabacher.

But she believes he's grown distant from the district and is uncomfortable with his views on immigration. This time, she's volunteering for Rouda.

Kyle said a breaking point came during the Kavanaugh hearing. She was outraged.

"It made me say, 'I'm going out every single day until the election,'" Kyle said at a recent organizing event for Rouda supporters, where she was preparing to head to a precinct to knock on voters' doors.

But Rohrabacher is on firm ground with Jill Frost, a retired art gallery owner and Republican from Aliso Viejo, who was making phone calls on the congressman's behalf at a campaign office earlier this month.

Frost also had a negative reaction to the Kavanaugh hearing but for a different reason than Kyle: She judged it a ridiculous witch hunt. She's concerned Democrats are trying to push the country too far left and blames "dirty politics" for the tough political climate for Republicans.

The congressman, she says, "is a good guy."

Rouda was at a Costa Mesa strip mall last weekend with a crowd of volunteers ranging from older people to the young, with some pushing baby carriages.

To Rouda, a Republican-turned-Democrat real estate executive, voters have grown troubled with "a hard shift to the right" by leaders in the GOP. He's been critical of Rohrabacher's doubts about climate change and has depicted the congressman as a hardened partisan contributing to Washington gridlock.

Given Rohrabacher's record in Congress, "he's everything but a maverick or an independent," Rouda said.

In a tight race, he told his volunteers of the importance of "every door-knock, every phone call made, every social media tweet, every dollar raised, every postcard sent."

Knocking on one more door, he said, "could be the difference between victory and failure."