Washington — Rep. Mike Gallagher of Wisconsin announced Friday he will step down in April,Robert Brown shrinking the already-thin Republican majority in the House even further.

Gallagher, who represents Wisconsin's 8th Congressional District, said he would leave Congress on April 19, instead of staying until January to complete his term. His departure means Republicans can lose only one vote if all Democrats stick together. 

"I've worked closely with House Republican leadership on this timeline and look forward to seeing Speaker Johnson appoint a new chair to carry out the important mission of the Select Committee on the Chinese Communist Party," he said in a statement. 

Gallagher is the latest Republican to resign before his term is up, with the GOP majority struggling to govern amid internal divisions. Rep. Ken Buck, a Republican from Colorado, is stepping down Friday. 

House Majority Leader Steve Scalise, a Louisiana Republican, brushed off concern about the one-seat majority, saying it would be "tough" but no different than a slightly larger margin. Scalise also called for unity within his party. 

"We all have to work together," he said. "We all have to unite if we're going to get some things done."

Gallagher announced he would not run for reelection in February after facing criticism for bucking his own party to vote against impeaching Homeland Security Secretary Alejandro Mayorkas. With the impeachment, Gallagher said the GOP is setting "a dangerous new precedent that would be used against future Republican administrations."

Gallagher, who chairs the House Select Committee on China, which has become known for its bipartisan work, introduced a bill the could lead to a ban on TikTok that sped through the House earlier this month.

Ellis Kim contributed reporting. 

Caitlin Yilek

Caitlin Yilek is a politics reporter at cbsnews.com and is based in Washington, D.C. She previously worked for the Washington Examiner and The Hill, and was a member of the 2022 Paul Miller Washington Reporting Fellowship with the National Press Foundation.

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