Daily Kos Elections’ project to calculate the results of the 2020 presidential election for all 435 congressional districts heads to the biggest state of them all, California, which contains multitudes. You can find our detailed county-by-county breakdowns here, and we also have a jumbo-sized map of the results you can explore. In addition, if you haven’t done so yet, you’ll want to bookmark our complete data set for all 50 states, which we're updating continuously.
Democrats wound up giving back four of the seven House seats they flipped from Republicans in 2018, but three of those involved surprisingly high levels of ticket-splitting rather than retrenchment at the presidential level. In the 25th District in northern Los Angeles County, Joe Biden’s 54-44 performance was an improvement on Hillary Clinton’s 50-44 showing, yet Republican Rep. Mike Garcia hung on to win a full term. However, he defeated Democrat Christy Smith by just 333 votes in their rematch—a margin of 0.1%, and far closer than his 55-45 win in a special election earlier this year.
The story was similar in the 39th District, which includes the San Gabriel Valley and northern Orange County. Biden scored a 54-44 win, a bit better than Clinton’s 51-43 take, but Republican Young Kim was nevertheless able to beat Democratic Rep. Gil Cisneros 50.6 to 49.4. Biden actually slipped several points in the 21st District in the heavily agricultural Central Valley, winning 54-44 compared to Clinton’s wider 55-40 victory, but Republican David Valadao narrowly unseated Democratic Rep. TJ Cox 50.4 to 49.6. In each of these, Republican House candidates ran nine to 10 points ahead of Donald Trump, indicating a sizable crossover vote in all three—a phenomenon both sides will want to study closely.
It was a different picture, however, in the 48th District, another seat in Orange County that Democrats were most worried about heading into the election—and with good reason, it turned out. Biden’s 50-48 margin was the same as Clinton’s 48-46 spread, and Republican Michelle Steel prevented Democratic Rep. Harley Rouda from winning a second term. Steel, though, only won 51-49, meaning she outran Trump by about four points, less than half what Garcia, Kim, and Valadao all managed.
While Biden’s 63-34 win statewide was superficially very similar to Clinton’s 62-32 victory, those toplines mask many differences. For starters, Biden’s record raw margin of 5.1 million votes was 833,000 votes greater than Clinton’s 4.3 million—which itself set the record at the time. Digging deeper, however, we can see that Democrats still lost ground in certain parts of the state. In fact, Biden’s share dipped double digits compared to Clinton’s in four districts: the 29th, 40th, 44th, and 51st.
This quartet shares something in common: All four seats are overwhelmingly Latino, a demographic that in many places shifted toward Trump. The district that saw the greatest movement was the 51st in San Diego, which is over 70% Latino. Biden’s 67-31 win represented a 13-point drop from Clinton’s 72-23 performance, though with his district still solidly blue, Democratic Rep. Juan Vargas won reelection easily. All of these districts, in fact, remain firmly Democratic. It’s worth watching, though, to see if this trend continues, or whether it was a unique artifact of the 2020 elections, perhaps owing to Trump’s status as an incumbent more than anything else.
At the other end of the scale, the district that saw the biggest gain for Democrats at the top of the ticket was the nearby 50th, located in inland San Diego County. Trump still carried it 53-45, but that was a seven-point decline from his 55-40 showing four years earlier. Given this district’s history as a rock-ribbed Republican enclave, former GOP Rep. Darrell Issa’s 54-46 victory over Democrat Ammar Campa-Najjar in this year’s open-seat race was relatively close, suggesting this seat could be in play in the future.
Another district Republicans will need to keep an eye on is the 22nd, around Fresno, which Trump won 52-46. That was a few points closer than his 52-43 win in 2016, and Republican Rep. Devin Nunes’ 54-46 win represented a notable tightening after a career of racking up ginormous victories every year until the 2018 blue wave.
At the same time, a number of seats Democrats were once worried about at the start of the decade have now become safely blue. That includes the 7th, 26th, 36th, and 52nd, all of which Democrats flipped in 2012 after the last round of redistricting.
And of course, redistricting lies just ahead once more, meaning boundaries across the state are likely to shift dramatically. California will once again rely on an independent commission to draw new lines as it did for the first time following the 2010 census, and any new maps must gain the support of Democratic, Republican, and unaffiliated commissioners.
However, commissions like this one, which was created via ballot initiative, have been under legal attack by conservatives. In 2015, the Supreme Court upheld the constitutionality of a similar commission in Arizona by just a 5-4 margin, and since then, the court has moved to the right. Should California’s commission get struck down, control over redistricting would return to the state’s heavily Democratic legislature.