Mike Garcia won reelection in California's 27th Congressional District, giving the Republican Party 218 seats in the House of Representatives and a majority in the 118th Congress next year.
Democrats have secured 209 seats in next year's Congress, with eight races still too close to call.
NBC News is projecting that Democrats will win five of those races while Republicans will win the other three, giving them a 221-214 seat advantage.
On Tuesday, Republican Minority Leader Kevin McCarthy won the Republican nomination for Speaker of the House. However, his victory is not assured because he still needs to secure enough support to get 218 votes.
While the Republican Party was able to secure a majority in the House, the Democrats held onto their majority in the Senate. They won 50 seats, while the GOP holds 49. Even if Herschel Walker defeats Senator Raphael Warnock in their upcoming run-off election, and the Senate is tied at 50, Democrats would have the tie-breaking vote with Vice President Kamala Harris.