Former President Barack Obama with then–congressional candidates (from left) Josh Harder, T. J. Cox, Gil Cisneros, Katie Porter, Harley Rouda and Mike LevinRingo H.W. Chiu / Associated Press

For all the focus since Election Day on the Republican Party’s precipitous decline in California, the true depth of the collapse is still only coming into focus. And so are the implications of that fall for the GOP’s prospects in other western states following the same trajectory of geographic and demographic change that have transformed California’s politics over the past 25 years.

When the next Congress convenes, Republicans will control at most eight of California’s 53 seats in the House of Representatives, down from 14 before the election. That number could fall to seven if GOP Representative David Valadao, who represents a Central Valley seat, cannot maintain a narrow lead over Democrat T. J. Cox that has steadily dwindled as officials have counted absentee and provisional ballots since Election Day.

Even if Valadao holds on, which looks increasingly doubtful, the eight Republican seats would leave the GOP controlling only 15.1 percent of California’s congressional delegation, the nation’s largest. That would be the smallest share of the state’s delegation that Republicans have controlled since 1883, according to figures provided by the California Target Book, a nonpartisan publication that analyzes state elections.

Even that earlier example was something of a fluke. Democrats won all six of California’s House seats in 1882, when Republicans nationwide lost almost three dozen seats in the first midterm after Vice President Chester A. Arthur replaced Republican President James Garfield, who had been assassinated in the summer of 1881.

But by 1884, when the state backed GOP nominee James Blaine in the presidential race, Republicans had rebounded to win five of California’s six seats.

Apart from that one slip in the early 1880s, Republicans since the Civil War have never fallen as far in the state’s congressional delegation as they have now. Even during the depths of the Depression, Republicans never fell below one-fifth of the state’s House seats, according to the Target Book data.

During the Watergate-backlash election of 1974, Republicans retreated to just over one-third of the state’s delegation, still more than double its share now. Before this month’s results, California Republicans had not held less than just over one-quarter of the state’s congressional seats at any point since 1938.

The GOP’s retreat in California long predated Trump, but there’s no question he has intensified and accelerated it. In the past two years, California House Republicans, under pressure from then–Majority Leader Kevin McCarthy of Bakersfield, compounded their risk by voting with Trump more reliably than their Republican counterparts in other blue-leaning coastal states such as New York, New Jersey, and Pennsylvania.

“They bet on Trump and they bet wrong,” says John J. Pitney, a Claremont McKenna University political scientist and former aide at the Republican National Committee.

It’s difficult to imagine now, but for most of its early history, California leaned Republican. Other than Franklin D. Roosevelt and Harry Truman, Democratic presidential candidates carried the state only three times from 1860 through 1960.

After Lyndon Johnson’s landslide win in 1964, Republicans again won California six straight times from 1968 through 1988, with native sons Richard Nixon and Ronald Reagan as the presidential nominee in four of those races.

In the late 19th century, California largely alternated between Republican and Democratic governors, but the GOP seized the advantage during the Progressive Era (through figures such as Hiram Johnson) and maintained it though the heart of the 20th century: Democrats controlled the governorship for only three terms from 1899 through 1974. And after the iconoclastic Democrat Jerry Brown won two terms as governor from 1974 through 1982, Republicans held the governor’s mansion for the next 16 consecutive years.

Over this long period, the balance of the state’s congressional delegation remained highly competitive. Republicans controlled most seats early in the 1900s, and again during the 1920s, a decade of GOP dominance nationwide. Democrats rebounded to win most of California’s seats under Roosevelt and Truman, but Republicans in turn revived to take a majority during the sharp postwar backlash against Democrats in 1946. Republicans then held most of California’s House seats until 1958, another bad midterm for the party. The Democrats maintained their advantage over the next 15 years, but their edge was narrow until the GOP’s Watergate collapse in 1974.

Still, as noted above, even then Republicans controlled about twice as much of the state delegation as it does now. Henry Waxman, a shrewd legislator who built a powerful Los Angeles–based political machine and was elected to the House in that 1974 Democratic wave, remembers those years as a period of close competition in the state.

“California as I was growing up was always a very competitive state between the two parties, and maybe even tilted Republican,” he told me. Riding Reagan’s landslide win in 1980, California Republicans clawed back to near-parity in the state’s congressional delegation.

But after the 1980 census, Democratic Representative Phil Burton, a master political operator, engineered a famous gerrymander that provided his party an advantage of about 10 seats, which it preserved throughout the 1980s. But even after that, Republicans recovered enough to evenly split the state’s delegation in the 1994 “Republican revolution” election, powered by a sharp nationwide backlash against President Bill Clinton’s first two years.

Yet in both parties, there’s near-unanimous agreement that that election marked the turning point for the California GOP. In 1994, Republican Governor Pete Wilson won reelection in part by successfully promoting the passage of Proposition 187, which denied public benefits to undocumented immigrants (including public schooling for their children). Though the courts eventually overturned much of the proposition, the effort alienated Hispanics, and even many Asian Americans, from the GOP.

“That was the pivotal moment,” says Bruce E. Cain, a Stanford University political scientist. “It had short-term benefits and long-term costs, and the party has never really recovered from that.”

Deepening the hole for Republicans during the 1990s was the post–Cold War decline of the state’s previously robust defense industry, which led to an exodus of right-leaning middle-class white voters.

With Bill Clinton and Al Gore easily carrying California in the 1996 and 2000 presidential races, Democrats reopened a comfortable advantage in the state’s congressional delegation. But the Democrat-controlled redistricting after 2000, ironically, may have slowed the state’s transformation: Though it locked in a three-to-two Democratic edge in the House delegation, it also drew safe seats for Republican incumbents.

Hardly any seats in California changed hands at all during the aughts. Redistricting “was always to help the party that was in [power] by securing their party’s members,” says Waxman, who was centrally involved in the process for Democrats beginning in the 1970s. “And when they did that, they secured the other party’s members as well, while giving them fewer seats.”

That entente broke down after Governor Arnold Schwarzenegger, who governed as a centrist, reform-oriented Republican and passed a ballot initiative in 2008 authorizing an independent commission to draw the district lines for Congress and the state legislature. The commission’s lines were first used in the 2012 election, and Republicans immediately dropped from 19 to 15 of the state’s congressional seats.

“It was a shock when we had an independent commission drawing the lines without regard to partisan consequences,” Waxman said. “That meant the Republicans who were [previously] given safe Republican districts suddenly had to run in districts that were Republican-leaning, but included others in the area as well, which were mainly aHispanic population.”

The final ingredient in the GOP collapse was Trump. From the start, his open appeals to white racial resentments and the fear of social change faced enormous resistance in diverse, culturally cosmopolitan California: He won less than 32 percent of the state’s vote in 2016. That essentially tied Alf Landon in 1936 as the weakest performance for a Republican presidential nominee in California since 1860. (William Howard Taft won even less of the vote in 1912, but only because Theodore Roosevelt, the former Republican president running as an independent, narrowly carried the state.)

But despite the unmistakable indication of Trump’s local unpopularity, the California GOP delegation locked arms around his turbulent presidency. That was partly due to pressure from McCarthy, who was looking to strengthen his own leadership prospects by solidifying his state delegation for Trump. (The House GOP caucus elected McCarthy as its leader last week.)

Those who fell in line included the seven Republican members in districts that had voted for Hillary Clinton over Trump in 2016. Two of those seven (Ed Royce and Darrell Issa) retired, but among the five that sought reelection, Steve Knight in exurban Los Angeles, Mimi Walters and Dana Rohrabacher in Orange County, and Jeff Denham and Valadao in the Central Valley all voted to repeal the Affordable Care Act, though California had expanded insurance under the law to more people than any other state.

All five also voted in December 2017 for Trump-backed legislation to override state gun-control laws and require California to honor permits to carry a concealed weapon granted in any state. And all but Rohrabacher voted for the GOP tax bill, even though its limits on state and local tax deductions threatened many upper-income voters in their own districts.

In all these ways, the California Republicans serving in Clinton-won districts voted more as if they were representing Alabama than swing seats in a state steadily becoming more Democratic. (Walters even told one interviewer that she thought Trump would win her affluent, diverse coastal district today and that she’d welcome a campaign appearance.)

Those choices emphatically caught up with them during this month’s sweep, when Democrats captured six of the Republican-held Clinton districts and remain within range on the seventh, held by Valadao.

Now most California Republicans see little prospect of regaining many, or perhaps any of these seats, so long as Trump’s stamp on the party repels both minority voters and college-educated white suburbanites, key growing constituencies throughout the state. They have been reduced to a literal handful of inland districts, almost entirely isolated from the state’s racially diverse and economically dynamic metropolitan areas.

“The national party has become a cultural brand that’s anathema to the demographics that have grown here,” says GOP consultant Rob Stutzman, the former communications director for Schwarzenegger.

With Republicans so marginalized in the state—Democrats this month restored supermajorities in both of the state’s legislative chambers and routed the GOP in all statewide races—just raising enough money to make their case may grow increasingly daunting for Republicans, Stutzman says.

California may be an extreme case of the political risks the GOP faces in a changing nation as Trump focuses the party’s message and agenda ever more narrowly on the priorities and cultural preferences of older, blue-collar, rural, and evangelical whites.

But Cain, the Stanford political scientist, notes that California is not unique, particularly in the west. Arizona, Nevada, Colorado, New Mexico, and even Utah and Texas are being reshaped by forces similar to those that have dyed California so deeply blue.

“You are seeing a transformation throughout the West now that looks a lot like what California went through,” Cain says. From one direction, he says, the region is being transformed by the “movement of white-collar workers in high-tech and related industries into urban areas. In California it was Los Angeles, it was the Silicon Valley.

“The same thing is now happening in Austin, Salt Lake City, in Albuquerque and Santa Fe and all these places.”

From the other direction, he notes, these states, like California, are also being reconfigured by immigration and growing racial diversity,
particularly among younger generations.

Cain and many other analysts correctly note that as the California GOP has contracted, it has generally positioned itself more overtly against these rising populations, both by maintaining a staunchly conservative agenda on social issues and also by embracing Trump’s open hostility to immigration (including his call for severe reductions in legal immigration and his pledge to build a border wall).

The most ominous prospect for national Republicans is the possibility that the California GOP’s slide into the ocean is only a preview of the growing strain they may face under Trump in the other southwestern states advancing along a similar trajectory of economic and demographic change.

“They have got themselves into this little echo chamber, and now Trump has added to that,” Cain says. “But obviously this blew up on the Republicans in California. And it’s blowing up on them in these suburban areas in the West and other parts of the country.”

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