Rep. Renee L. Ellmers (R-N.C.) lost her bid for reelection Tuesday, becoming the first GOP congressional incumbent to lose a seat in 2016.

Ellmers, who was elected in 2010 amid the tea party takeover of the House, lost in a special primary election to Rep. George Holding (R-N.C.) in North Carolina’s 2nd Congressional District, which includes suburban and rural Raleigh.

Holding won with over 53 percent of the vote with 96 percent of precincts reporting, according to the Associated Press. Ellmers was barely clinging to second place ahead of Greg Brannon, edging him by little more than 200 votes.

Brannon previously ran for Senate in 2014 — earning an endorsement from Sen. Rand Paul of Kentucky — and lost to Sen. Thom Tillis (R). Brannon ran again this year, losing to Sen. Richard Burr (R-N.C.) in the March Senate primary.

Holding used to represent the 13th Congressional District but chose to run in the 2nd district after court-mandated redistricting took effect earlier this year, prompting an incumbent-versus-incumbent showdown.

In New Jersey’s 1st Congressional District, another incumbent — Rep. Donald W. Norcross (D) — succeeded in moving on to the general election. Norcross beat Democratic insurgent Alex Law, a 25-year-old Bernie Sanders supporter, with 70 percent of the vote with 92 percent of precincts reporting.

Like Sanders, Law generated a grass-roots campaign and small donations, targeting what he called “the political machine” — a reference to the Norcross family’s deep roots in New Jersey politics. Norcross’s brother George Norcross is an influential leader in the Democratic Party in South Jersey.

In California, statewide races are a jungle primary, which means candidates of all parties faced off on Tuesday’s primary, and the top two vote-getters advanced to the general election in November.

California has seen a record 17.9 million voters register ahead of the primary. Voter registration increased for both the Democratic and Republican parties, though a greater percentage registered as Democrats during the final stretch before the primary. Nearly 650,000 people registered in the last 45 days leading up to the registration deadline. Of the people who registered during the final rush, 76 percent were Democrats, according to the California Secretary of State’s office.

Several House GOP incumbents could be impacted by the surge in Democratic voter registration. Though they all appeared poised to advance to the general election as of late Tuesday, the real test will come in November, when the increased number of registered Democrats could help propel their Democratic challengers to victory. 

The most vulnerable Republican in that category is Rep. Steve Knight in the 25th Congressional District, which includes northern Los Angeles and Ventura counties. That is largely due to an increase in Latino and Democratic voters in the district, said David Wasserman, a nonpartisan political analyst for the Cook Political Report.

In 2012, the number of registered Republicans in Knight’s district outnumbered Democrats by about 14,000; as of May 2016, Democrats outnumber Republicans by about 3,400.

On Tuesday, Knight finished first with 50.4 percent of the vote with 7 percent of precincts reporting. He will likely face Democrat Bryan Caforio, an attorney, who was in second with 27.8 percent of the vote.

Other House Republicans who may be at risk, but probably less so, are Reps. Jeff Denham and David Valadao, who represent parts of the Central Valley. There, it has been harder to register transient Latinos who work in the agriculture labor force, Wasserman said.

Denham, who represents the 10th Congressional District, appeared close to finishing first with 48.8 percent of the vote with 40 percent of precincts reporting. He will likely face Democrat Michael Eggman, a farmer, who got 27.6 percent of the vote.

Valadao, who represents the 21st Congressional District, came in first with 60.4 percent of the vote with 22 percent of precincts reporting. Daniel Parra, a computer systems analyst and city councilmember in Fowler, Calif., was second with 21.2 percent of the vote.

Rep. Darrell Issa’s reelection is another one to watch. The 49th Congressional District includes parts of San Diego and Orange counties. Issa has been a staunch Trump supporter and, come November, there could be blowback from voters that could benefit Democratic challenger Doug Applegate.  

Issa was leading as of late Tuesday with 53.9 percent of the vote with 7 percent of precincts reporting, followed by Applegate, an attorney and retired Marine colonel, who received 43 percent of the vote.

House Majority Leader Kevin McCarthy was on track to advance to the general election representing the California’s 23rd district. As of late Tuesday, he had 59.2 percent of the vote with 22 percent of precincts reporting. McCarthy will likely face Democratic challenger Wendy Reed, a businesswoman, who garnered 25.4 percent of the vote.

Even though McCarthy did not face a well-funded challenger Tuesday, he nonetheless spent $2.1 million between Jan. 1 and mid-May to strengthen his standing, running TV and radio ads in the final days before the primary.

In the Bay Area, Democratic incumbent Rep. Mike Honda looks to be once again facing challenger Ro Khanna, an attorney who nearly beat him in 2014, come November. As of late Tuesday, Honda and Khanna were almost neck-in-neck in California’s 17th Congressional District, with Honda narrowly edging out Khanna, 38.4 to 37.6 percent, with 23 percent of precincts reporting.

In North Carolina, Ellmers recently became the target of intense opposition from conservative groups who once supported her initial rise to office, including the Koch-funded Americans for Prosperity, Club for Growth and antiabortion organizations. They say Ellmers failed to follow through on the commitment to conservative values she promoted when first elected.

To add another wrinkle to the unusual race, Donald Trump endorsed Ellmers on Saturday, the first time the presumptive Republican presidential nominee has weighed in on a congressional race. Ellmers was the first woman in Congress to endorse Trump in March.

Ellmers’s loss is a victory for some of the same forces that elevated her to office to begin with.

When she ran six years ago, Ellmers joined the bus tour hosted by AFP that traveled the country railing against President Obama’s health-care law. She later spoke at rallies hosted or co-sponsored by the group and promoted AFP events. In 2010, she even nabbed an endorsement from Sarah Palin.

This year, AFP was one of the main players in the costly crusade that successfully ousted Ellmers in the group’s premier foray to defeat an incumbent in a Republican race. Others that took on the congresswoman include the Club for Growth and the antiabortion National Right to Life and Susan B. Anthony List.

This constellation of conservative groups had a single message for voters: Their congresswoman, they said, has “gone Washington.” They took firm issue with Ellmers’s vote to renew the Export-Import Bank and her support for the 2016 budget and allege that she is too close to the House GOP leadership.

“Renee Ellmers — in 2009 and 2010, she came to AFP events and touted her conservative values,” said AFP president Tim Phillips before the primary. “And she hasn’t kept her word on that.”

Last month, Ellmers acknowledged she had “become this poster child” for conservative fury and argues that’s because she refused to do the bidding of special interests in Washington.

“Apparently [it’s] because I’m not beholden to any of them. I’m not beholden to my House Republican leadership. I am not beholden to the special interest groups,” she said in an interview before a town hall here last week.

“I absolutely refuse to feel the pressure they put on other members to vote the way they want them to vote. I don’t care about the scorecards that they keep. And because I have been so vocal about it, I believe this is the reason they’re coming at me. Because I have been pointing out what so many others are too afraid to say, which is that special interest groups want to control members of Congress.”

Holding also had a significant financial advantage. He raised nearly $295,000 in April and May, compared to Ellmers, who raised just $27,000 during the same period, according to FEC filings.

The American Foundations Committee, a super PAC, spent $189,000 backing his campaign and $113,000 opposing Ellmers’s, according to the Center for Responsive Politics. The group also backed Holding’s 2012 campaign, and a number of its donors are members of the Holding family, which has maintained a controlling stake in Raleigh-based First Citizens Bank for three generations.

Club for Growth’s super PAC spent about $700,000 on television and digital ads to defeat Ellmers. They criticized Ellmers for being “too liberal for North Carolina” and says she’s “become part of the problem in Washington.”