Rep. Liz Cheney, the highest-ranking woman in House Republican leadership, announced Thursday that she will not run for the open U.S. Senate seat in Wyoming, opting instead to seek reelection in the House.

“I believe I can have the biggest impact for the people of Wyoming by remaining in leadership in the House of Representatives and working to take our Republican majority back,” Cheney said in a statement. “I will not be running for the Senate in 2020. I plan to seek reelection to the House of Representatives.”

News of Cheney’s plans was first reported by the Casper Star-Tribune.

Cheney, a daughter of former vice president Richard B. Cheney, is House Republican Conference chairwoman, the No. 3 spot in House GOP leadership. She has risen swiftly through her party’s ranks since first winning election to the House in 2016, and for months she had left the door open to a bid to succeed retiring Sen. Mike Enzi (R-Wyo.).

Cheney had pursued a Senate bid in 2014 but abruptly ended her campaign after only five months, citing “serious health issues” that had arisen in her family.

Remaining in the House means that the 53-year-old mother of five will maintain a Cheney family tradition — her father represented the state’s at-large district for a decade, rising to minority whip before leaving Congress to serve as defense secretary.

It will also give Cheney an opportunity to someday compete to become the first Republican female speaker.

The ranks of female lawmakers swelled to 102 after the 2018 elections, their highest number. But among House Republicans, that trend is heading in the opposite direction. There are only 13 women in the House GOP caucus, down from nearly twice as many before the 2018 midterms — a development that has prompted alarm from some GOP women who have warned that their party is facing a crisis.

Rep. Carol Miller (W.Va.) is the lone Republican woman in the freshman class, and the retirement next year of Rep. Susan Brooks (Ind.) — who had prioritized mobilizing GOP women to run for office — has prompted some Republicans to reflect on their party’s difficulties in recruiting women as both candidates and voters.

In her statement Thursday, Cheney kept her focus on Democrats, whom she repeatedly derided as “socialists” who “are threatening our liberty and freedom.”

“They must be stopped,” Cheney said. “Our nation is facing grave security challenges overseas and the House Democrats are working to weaken our president and embolden our enemies.”

Cheney is the second major Republican in a month to turn down a chance at a seat in the Senate, two blows that will probably not affect the chase for the majority but raise questions about the diminished stature of the Senate.

Secretary of State Mike Pompeo, courted for months by Senate Republicans, informed Senate Majority Leader Mitch McConnell (R-Ky.) this month that he would not run for the seat of retiring Sen. Pat Roberts (R-Kan.).

Both the Kansas and Wyoming seats are expected to remain in GOP hands, but Pompeo and Cheney would have entered those races as very strong favorites and probably could have held the seats for years to come.

Cheney’s colleagues in House Republican leadership thanked her Thursday for her decision to run for reelection.

At his weekly news conference, House Minority Leader Kevin McCarthy (R-Calif.) described Cheney’s announcement as “very good news” and hailed her as “a fighter” and “a powerful voice for conservatives.”

“What you need to read into it is there’s a real chance that we’re going to win the majority,” he told reporters. “The idea that our conference chair had an opportunity to go to the Senate and she chose to stay here to help us win the majority — I thank her for that.”

Republicans have faced questions about their ability to reclaim the House, as 26 GOP members have announced they would retire at the end of their term, around the same number at this point in the 2018 election cycle when the party lost the majority.

Colby Itkowitz contributed to this report.