Lookout Mountain, Georgia - Republican Clay Fuller won Tuesday's special election runoff to serve out the rest of former Representative Marjorie Taylor Greene's term in the House.

Fuller claimed victory in the race to represent Georgia's 14th congressional district, winning 55.9% of the vote, according to the Associated Press.

Democratic challenger Shawn Harris, a retired Army brigadier general and cattle rancher, got 44.1%.

"Thank you to the voters of GA-14 for your trust and support! The real work begins!" Fuller posted on X on Tuesday.

Fuller and Harris advanced to a runoff after no candidate won a majority of the vote in March's all-party primary.

The Republican candidate – a district attorney and former White House fellow – had received the backing of President Donald Trump in his bid to replace Greene.

"As your next Congressman, Clay will fight tirelessly to Grow the Economy, Cut Taxes and Regulations, Promote MADE IN THE U.S.A., Unleash American Energy DOMINANCE, Keep our Border SECURE, Stop Migrant Crime, Safeguard our Elections, Champion School Choice, and Defend our always under siege Second Amendment," Trump wrote in an endorsement message.

Greene announced her retirement from Congress last November, effective January 5. The former Trump acolyte has recently broken with the president over his violent foreign policy, handling of the Jeffrey Epstein files, and failure to rein in the affordability crisis in the US.

On Tuesday, Greene called for Trump's removal from office after he threatened to wipe out a "whole civilization" in his war on Iran. The president ultimately backed off after a two-week ceasefire deal was reached.