RINGGOLD, GA — Republican congressional candidate Clay Fuller just gave House Speaker Mike Johnson a little bit of breathing room as the GOP clings to a razor-thin majority in Congress.Fuller, who was backed by President Donald Trump, on Tuesday defeated Democrat Shawn Harris in a special election to fill the empty U.S. House seat in Georgia's solidly red 14th Congressional District, the Associated Press reported."He was the difference maker," Fuller told Fox News Digital following his victory, as he pointed to Trump. "He was the key factor in us winning…. Our results prove that President Trump means a ton to Georgia-14."The seat was left vacant when MAGA firebrand Republican Rep. Marjorie Taylor Greene stepped down at the beginning of January. Greene quit Congress with a year left in her term, after a bitter falling out with Trump.The special election came as Republicans cling to a razor-thin 218–214 majority in the House. The GOP was under the gun to make sure the Democrats didn't pull off an upset in the special election, in a district in northwest Georgia that Trump carried by a whopping 37 points in his 2024 presidential victory.PRIMARY PAUSE, POLITICAL FIRESTORM: HIGH-STAKES ELECTIONS THIS MONTH TAKE CENTER STAGE"It's extremely crucial, and we need the reinforcements," Fuller told Fox News Digital on the eve of the runoff election.Fuller, a local district attorney and a lieutenant colonel in the Air National Guard who's served in the Air Force since 2009, added, "I think the voters in Georgia 14 understand that, and they're looking forward to sending a MAGA America first fighter up on Capitol Hill to support that agenda."TRUMP HITS CAMPAIGN TRAIL IN KEY BATTLEGROUND AS RACE TO REPLACE MARJORIE TAYLOR GREENE HEATS UPAsked if he was concerned that MAGA supporters would sit out what was expected to be a low-turnout election since the president is not on the ballot, Fuller said Trump voters "would crawl through glass to make sure they have a representative up there that fights for them and fights for President Trump."Harris, a cattle farmer who spent four decades in the military and retired as an Army brigadier general, needed the support of crossover Republicans in order to pull off an upset."I am a Democrat, but I'm not tied to the party," Harris highlighted as he spoke with Fox News Digital on Monday. And Harris argued, "My opponent, Clay, cannot say that. He actually sold his soul to President Trump."Harris narrowly edged Fuller amid a field of 17 candidates, including 12 Republicans, in the first round of voting in early March. Since no candidate topped 50%, Harris and Fuller advanced to Tuesday's runoff.HEAD HERE FOR THE LATEST FOX NEWS REPORTING FROM THE CAMPAIGN TRAILThe congressional seat — which stretches from Atlanta's outer suburbs to the state's northwest borders with Alabama and Tennessee — was left vacant when Greene quit Congress with a year left in her term, after a very public falling out with Trump mostly over her push to release the Jeffrey Epstein files.While Greene remains popular among Republicans in the district, Fuller said the voters he talked with on the campaign trail were "focused on the fights of the future, not anything that had happened in the past."Asked if he spoke with Greene, Fuller said he "reached out to Rep. Greene, had conversations with her and got advice on the district, and I'll keep those conversations confidential."Harris, who as a first-time candidate lost to Greene by nearly 29 points in her 2024 re-election, emphasized that he wasn't "running against Marjorie Taylor Greene anymore," and that his name "carries more weight than any other name in this district."With the vast majority of votes tallied, Harris trailed Fuller by roughly 12 points, which was a significant improvement over his 2024 performance against Greene.Democrats touted their over performance in the special election runoff."Tonight, in the deepest-red congressional district in Georgia – and despite more than $1.5 million in spending by Republicans to defend this Trump +37 seat – Democrat Shawn Harris notched a jaw-dropping more than 20-point over performance in Marjorie Taylor Greene’s backyard," Democratic Party of Georgia Chair Charlie Bailey said in a statement.And Democratic National Committee Chair Ken Martin highlighted that Shawn Harris ran a fearless campaign in the reddest district in all of Georgia, delivering a double-digit overperformance."Martin argued, "Enthusiasm for Democrats is growing everywhere. We’re closing the gap and Republicans are absolutely terrified."Democrats have repeatedly showcased their slew of special election victories and over performances in the nearly 15 months since Trump returned to the White House.But Fuller pushed back on the Democrats' messaging."They lost. They've got to call me congressman, and they poured in millions of dollars, just lit millions of dollars on fire, and still got crushed," he argued, in his Fox News Digital interview.Fuller doesn't get much time to enjoy his victory.He'll be running in next month's primary in Georgia as aims to be the party's nominee in the district in November, when he'll seek a full two-year term in Congress.And Harris said he would be running again as well in the midterms.In a statement, Harris emphasized, "This wasn’t the result we wanted, but the message is clear — people here are ready for leadership that puts them first. The fight continues. On to November!"