LOS ANGELES (AP) — Republican Michelle Steel defeated first-term Rep. Harley Rouda on Tuesday in a Southern California district, only the second time in more than two decades that a GOP candidate in the state has defeated an incumbent Democrat.

Rouda captured Orange County’s 48th District in 2018 from longtime Republican Rep. Dana Rohrabacher, part of a Democratic sweep of seven House seats in California that year.

Steel said the vote this year showed the American dream “is alive and well in Orange County.” She vowed to fight for lower taxes, small businesses and their workers, and to defeat the coronavirus.

“I stand ready to work with both parties,” she said in a statement.

Steel joins Washington state’s Marilyn Strickland as the first Korean American women elected to Congress. Strickland, a Democrat, last week won the open 10th Congressional District southwest of Seattle.

Steel won about 51% of the votes in a year when Joe Biden trounced President Donald Trump in the state. Trump was backed by about 33% of California voters.

Steel, who heads the Orange County Board of Supervisors, benefited from the district’s Republican registration edge and also surmounted widespread distaste for Trump in the strongly Democratic state.

In addition to Steel's victory, Republican candidates are leading in two other undecided races in Democratic-held districts:

Young Kim is running ahead of Democratic Rep. Gil Cisneros in the 39th District anchored in Orange County, and Republican former Rep. David Valadao is leading Democratic Rep. TJ Cox in the Central Valley's the 21st District.

In the 25th District north of Los Angeles, Republican Rep. Mike Garcia is narrowly trailing Democrat Christy Smith. And Republican former Rep. Darrell Issa captured the conservative-leaning 50th District, which was vacated earlier this year by GOP Congressman Duncan Hunter after he pleaded guilty to a federal corruption charge.

The campaign involving Steel and Rouda was marked by nasty campaign ads and finger-pointing. Steel argued that Rouda would raise taxes, while the incumbent depicted Steel as a corrupt politician.

Rouda indicated he would challenge Steel in 2022 and lamented the “toxicity” in politics that he said was threatening democracy.

“Politics that tears America apart and turns us against each other is unsustainable. We saw it firsthand in this election,” he said.

Orange County this year is one of the crucial House battlegrounds in California and the U.S.

Known for its beaches, suburbs and sunshine, the county was a foundational block in the rise of the modern conservative movement and President Ronald Reagan likened it to a Republican heaven. But like much of the state, the district has been in political transition, with its once largely white population becoming more diverse while its percentage of registered Republicans slipped.

In a sign of dramatic change, Democrats seized four House districts all or partly in the county in 2018, placing a vast stretch of the Los Angeles metropolitan area under Democratic control in the U.S. House. Democrats now outnumber registered Republicans in the county by about 2 points.

Fred Whitaker, who heads the Republican Party of Orange County, said Steel’s victory “is the start of the Orange County comeback for Republicans.”

Steel, who is married to Republican National Committeeman Shawn Steel, emphasized her work on the county board and longtime opposition to higher taxes, while also criticizing Democratic leadership in state government.

Rouda, a former businessman, sought to position himself as a moderate problem-solver and highlighted his efforts to work across party lines.