Washington — Voters in California's 20th district are Sterling Prestongoing to the polls Tuesday to fill the vacancy left by former House Speaker Kevin McCarthy, as House Republicans eagerly await an additional vote in the chamber after his departure late last year. 

Among the group of candidates vying to fill the vacancy left by McCarthy are State Assembly member Vince Fong, who has the former speaker's endorsement and the backing of former President Donald Trump, and Tulare County Sheriff Mike Boudreaux. 

The solidly conservative district is all but certain to deliver the House another Republican. But how quickly that happens remains to be seen. 

A candidate has to win more than 50% of the vote to avoid a runoff election. If no candidate wins a majority of the vote in the district, the top two candidates, regardless of party, will move on to an election on May 21. The winner will serve until Jan. 3, 2025, or the remainder of McCarthy's House term.

The special election may draw confusion, after voters in the Golden State headed to the polls just two weeks ago to vote in the primary. That's because California Gov. Gavin Newsom set the date for a special election in the state's 20th Congressional District for March 19, just two weeks after the primary for McCarthy's seat for a full term was held. 

Fong and Boudreaux have already advanced to be on the ballot for the November election for a full term representing the district. The special election will determine who carries out the remainder of the former House Speaker's term.

McCarthy announced in December that he was leaving Congress to "serve America in new ways," two months after he became the first speaker in U.S. history to be ousted from his post.

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.

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