By Adam Levy and Ethan Cohen, CNN

(CNN) -- Republican Julia Letlow won the special election in Louisiana's 5th Congressional District Saturday night, becoming the first Republican woman elected to Congress from the state.

Letlow will take the seat that her late husband Luke, who won last year's election but died in December after being diagnosed with Covid-19, was never able to hold.

The first-time candidate avoided a runoff by securing a majority of the vote among the 12-person field, which means she'll soon bolster the already record-breaking 30 Republican women in the House this year.

A number of prominent Republicans had rallied behind her after she announced her campaign for the open seat in the conservative district. Former President Donald Trump, House Republican Leader Kevin McCarthy and Louisiana GOP Rep. Steve Scalise -- the No. 2 House Republican -- all endorsed her out of the nine Republicans running for the seat.

Letlow, a university administrator who wrote a doctoral dissertation on grief, jumped into the race in mid-January after the governor called a special election to replace her husband. She benefited from having a campaign team already in place and far outraised her opponents. Under Louisiana's jungle primary system, candidates of all parties run together on one ballot.

In an interview before the election, Letlow told CNN she would have joined the majority of the House Republican Conference in objecting to the certification of the presidential election on January 6, and she supports her state party's decision to censure GOP Sen. Bill Cassidy for his vote to convict Trump in his impeachment trial earlier this year.

Runoff in 2nd District

Democrats Troy Carter and Karen Carter Peterson advanced to an April 24 runoff in the special election for Louisiana's 2nd Congressional District, CNN projected Saturday.

The winner of the runoff will fill the seat vacated by Democrat Cedric Richmond, who resigned in January to join the Biden administration.

Carter and Carter Peterson, who are not related, are both Louisiana state senators representing New Orleans.

Carter is the senate minority leader and received Richmond's endorsement before he resigned from Congress. Carter Peterson served in the Louisiana House for a decade before joining the Senate in 2010 and has also served as vice-chair of the Democratic National Committee.

Carter Peterson finished with the second-most votes, receiving about 1,400 more votes than Democrat Gary Chambers, Jr., as of late Saturday night.

This story has been updated Sunday with additional context.