West Virginia Republican Gov. Jim Justice won the state’s open Senate seat Tuesday, NBC News projects, moving Republicans one step closer to flipping the balance of power in the chamber.

Justice faced little competition from Wheeling Mayor Glenn Elliott, a Democrat, in a race that Republicans were heavily favored to win after the retirement of independent Sen. Joe Manchin, who left the Democratic Party in May.

With Justice's victory, the GOP needs to flip just one more seat to win control of the Senate if Vice President Kamala Harris holds the White House for the Democrats. If former President Donald Trump wins, the GOP is poised to control the Senate if no other seats change hands, since the vice president breaks ties in the chamber.

Justice won election as governor in 2016, the same year Trump won the state by more than 42 percentage points. At the time, Justice ran as a Democrat, beating his Republican opponent by 7 percentage points.

He announced he was leaving the Democratic Party one year later, standing alongside Trump at a campaign rally. After easily winning re-election in 2020, speculation quickly began to mount as to whether the term-limited governor would eye a Senate bid in 2024.

Justice launched his campaign in 2023, as Manchin publicly refused to commit to running again. After months of publicly clashing with his party, Manchin announced he wouldn’t seek re-election.

While the governor had been the pick of the Republican establishment, he faced a primary challenge in the spring from GOP Rep. Alex Mooney, who was backed by the conservative Club for Growth. But Justice cruised to victory, defeating Mooney by 35% points in May, and has faced little political opposition since.