The Democrat Katie Porter now holds a slim lead in California's Forty-Fifth Congressional District, in Orange County.Jae C. Hong / AP

LOS ANGELES—Democrats had already reclaimed the House of Representatives before California’s election returns came in last week, but since Election Day, the party has racked up a nice bonus here: After the counting of vote-by-mail ballots, Democrats appear to have won four of the state’s six most competitive congressional races. In the remaining two, a Democrat has just taken a slim lead in one, while another Democrat barely trails in the other.

That means California is bluer than ever, with Lieutenant Governor Gavin Newsom becoming the first Democrat since 1887 to succeed a fellow partisan as governor of this state, and with “California Democrats Set to Dominate Congress,” as a Breitbart News headline put it with alarm. Not only is Nancy Pelosi, the newly reelected representative of California’s Twelfth District, poised to resume the speakership, but vocal critics of Donald Trump in the state’s newly expanded 43-member Democratic delegation will be in line to chair key committees.

Just imagine what grief “low IQ” Maxine Waters, as Trump calls her, might cause the president as the chair of the House Financial Services Committee, which controls banking regulation. Or the difference it will make to have Adam Schiff as the chair of the Intelligence Committee, replacing Devin Nunes, one of Trump’s most reliable supporters.

Zoe Lofgren, a twelve-term incumbent from San Jose, will likely head the House Administration Committee and the subcommittee on immigration, while Anna Eshoo, a 26-year veteran from Palo Alto, seems poised to chair an energy and commerce subcommittee.* Mike Thompson, a 10-term member from St. Helena in Napa Valley, will probably head up the Ways and Means Committee’s subcommittee on health care.

More trouble for Trump could come from the state’s Democratic attorney general, Xavier Becerra, appointed two years ago to fill the vacancy created by the election of Kamala Harris to the Senate. He easily won election to a full term, and seems ready to continue the dozens of lawsuits he has already filed contesting Trump-administration legislative and regulatory policies on issues from climate change to immigration. No Republican has won statewide office here since Governor Arnold Schwarzenegger in 2006.

All that is on top of the Democrats’ strong performance in Republican-leaning House districts where the party hoped to make gains, fueled by Trump’s unpopularity here. So far, four Democrats have officially won: Katie Hill, who beat the GOP incumbent Steve Knight in a district in northern Los Angeles County; Mike Levin, who defeated Diane Harkey for an open seat in Orange and San Diego Counties vacated by the retirement of Darrell Issa; Harley Rouda, who beat the 30-year Republican incumbent Dana Rohrabacher in another Orange County district; and Josh Harder, who defeated the Republican incumbent Jeff Denham in the state’s agricultural Central Valley.

At the same time, two races in which Republicans held the edge on Election Night have tightened dramatically, as mail ballots of younger and late-deciding voters are counted. In an Orange County district, the Democratic challenger Katie Porter has opened a slight, 260-vote lead over the GOP incumbent Mimi Walters. Similarly, in a neighboring district that spans three counties and includes the birthplace of Richard Nixon, Gil Cisneros is trailing the Republican Young Kim, a former aide to the retiring representative Ed Royce, by just over 700 votes, half the margin on Election Night, or 50.2 percent to 49.8 percent.

Most of these six hotly contested races have been close. Only Levin racked up a comfortable five-point Democratic victory. Meanwhile, in a seventh district that some had thought might be competitive, Representative Duncan Hunter, a Republican incumbent who is under indictment for misusing campaign funds in a district in San Diego and Riverside Counties, easily defeated his half-Latino, half-Arab challenger, Ammar Campa-Najjar, a devout Christian and former Obama White House aide, after running a strident anti-Muslim campaign in the final stretch.

Bill Carrick, a veteran Democratic strategist here, noted three factors in the Democrats’ strong performance: anti-Trump sentiment, the recruitment of “good candidates and nonpoliticians,” and demographic changes. “At the end of the 10-year reapportionment cycle, congressional districts move closer and closer to the overall California demographic norm,” he said.

But if Walters and Kim wind up winning, it will be because Republicans still have an edge in voter registration in such districts, where Hillary Clinton beat Trump in 2016. And candidates like Walters and Kim, the GOP contenders who ran most strongly, did not position themselves as hard-edged Republicans, while their opponents, Cisneros and Porter, ran more or less as unabashed liberals in districts where that meant an uphill climb. For example, Walters’s district still has about a nine-point GOP edge in registered voters, and Porter, a law professor at the University of California at Irvine and a Harvard Law School protégé of Senator Elizabeth Warren, has gambled that she could win by campaigning on issues like “Medicare for all.”

The math in such districts is growing steadily more favorable for the Democrats, and the GOP will have to defend its latest victories again in just two years, when a presidential election is likely to inspire higher turnout among the minority and younger voters who tend to underperform in the midterms.

In the near term, California’s newly empowered congressional Democrats might cause no end of headaches for Trump. Schiff has made it clear that while leading the Intelligence Committee he intends to dig into Trump’s complex ties to Russia, an inquiry that has been stymied in the past by Nunes’s unwavering fealty to the White House.

And while Trump’s virulent anti-immigration rhetoric in this campaign’s homestretch may have helped his party hold the Senate this year, California history provides a vivid reminder that short-term political gains can sometimes turn into long-term losses. Twenty-four years ago, the state’s incumbent Republican governor, Pete Wilson, rode to reelection partly on the back of Proposition 187, a ballot measure to deny state services to undocumented immigrants. But the backlash against that proposal among the state’s growing Latino electorate also planted the seeds of the decline of the Republican Party in the state—a decline that continued apace last week.


*This article originally misstated the number of terms Representative Lofgren had served. She is a twelve-term incumbent.

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