Former Speaker Kevin McCarthy speaks during an event awarding House Clerk Cheryl L. Johnson with the 2023 Freedom Award, Feb. 13, 2024. (Aaron Schwartz/NurPhoto via Getty Images)

(WASHINGTON) — The special primary election to succeed former House Speaker Kevin McCarthy unfolded on Tuesday in California’s 20th Congressional District.

ABC News projects that State Assemblyman Vince Fong will advance to the special general election in May.

The race will fill a critical vacancy for Republicans who are already dancing on the knife’s edge of a microscopic majority in the House.

The special election, open to all registered voters in the district, is set to determine who will finish the remainder of McCarthy’s term. He left Congress at the end of December.

Fong, endorsed by McCarthy and former President Donald Trump, and Tulare County Sheriff Mike Boudreaux had established themselves as the front-runner candidates in the special primary.

Nine candidates were on the ballot.

Back in Washington, a runoff could prove frustrating to congressional Republicans, who have recently faced a wave of high-profile retirements, including McCarthy and, more recently, Colorado Rep. Ken Buck, who announced that he would leave the House at the end of the week.

Currently, Republicans can only afford to lose two members of their conference on any party-line vote on legislation.

As of Tuesday’s election, five House Republicans, including Buck, had resigned or been removed from office during this Congress.

Beyond McCarthy’s seat, two other Republican vacancies remain unfilled and one of those five overall seats, formerly held by expelled New York Rep. George Santos, is now held by Democrat Tom Suozzi, leaving Republicans with 219 seats to Democrats’ 213.

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