Sen. Bill Nelson, a Florida political icon who first arrived on Capitol Hill in the decades when Democrats dominated this presidential battleground state, conceded his bitterly close re-election bid to Republican Rick Scott after a bruising recount left Nelson thousands of votes short of the outgoing governor.

Nelson gave up his quest after days of tense and often acrimonious recounting wrapped up at midday Sunday, when Florida's counties had to turn in their official results. Florida will not officially certify the final results until Tuesday, but the totals showed Nelson trailing Scott by more than 10,000 votes.

“It has been a rewarding journey as well as a very humbling experience,” Nelson said in a videotaped statement. “I was not victorious in this race but I still wish to strongly reaffirm the cause for which we fought: A public office is a public trust.”

The close of nearly two weeks of high political drama in the presidential swing state likely spelled the end of the political career of the 76-year-old Nelson. First elected to the U.S. House 40 years ago, Nelson had been a Democratic survivor in an era when Republicans swept to power in Florida in the '90s. He was first elected to the U.S. Senate in 2000 and was making his fourth bid at Senate re-election.

A Florida native with a distinct twang, Nelson fought a hard race against Scott, a multimillionaire businessman and relative newcomer to the state who had been urged to run by President Donald Trump. A Scott victory will help Republicans boost their Senate majority.

This marked the third time Scott, who did not jump into politics until eight years ago, has barely edged a Democratic rival.

“Now the campaign truly is behind us, and that's where we need to leave it,” Scott said in a statement after official results were posted. “We must do what Americans have always done: come together for the good of our state and our country. My focus will not be on looking backward, but on doing exactly what I ran on: making Washington work.”

Trump congratulated Scott on Twitter: “From day one Rick Scott never wavered. He was a great Governor and will be even a greater Senator in representing the People of Florida.”

Nelson was seen as a moderate, rarely making waves or gaining much national exposure as he focused on Florida-specific issues. One of his more notable moments came when he flew on Space Shuttle Columbia while serving in Congress.

Florida's other senator, Republican Marco Rubio, said he would miss working with Nelson.

“I knew Bill Nelson not just as a Democratic senator, but also as a man of genuine faith, integrity and character,” Rubio said in a statement. “A man who served our country with a dignity that is increasingly rare in our modern politics.”

This marked only the second electoral defeat of Nelson's long political career. He lost a Democratic primary for governor to eventual winner Lawton Chiles in 1990.

After it became clear the Senate race would head to a legally required recount, Nelson and Democrats filed several lawsuits that challenged everything from Scott's authority over the state's election division to deadlines for mail-in ballots. Amid the recount, Scott suggested that some county election officials were allowing fraud to occur.

Republicans raised questions about how some South Florida election officials were counting the ballots. The South Florida Sun-Sentinel reported late Sunday that one of those officials, Broward County Supervisor of Elections Brenda Snipes, had presented a resignation letter to step down in January. The report cited an attorney who works as counsel to the Broward elections office, Burnadette Norris-Weeks, but Snipes couldn't immediately be reached for comment.

State officials had ordered a manual recount after a legally required machine recount showed that Scott led Nelson by about 12,600 votes. More than 8 million voters cast ballots in the race.

Scott ran a harsh campaign against Nelson, calling the incumbent ineffective and out of touch.

While the two disagreed on such key issues as gun control, health care and the environment, they focused primarily on character and competence. Scott repeatedly bashed Nelson in TV ads paid for by more than $60 million of his own wealth.

Meanwhile, Nelson branded Scott as a Trump follower who had used the governor's office to pad his wealth.

Nelson and his allies also ran ads that questioned Scott's ethics, pointing to his ouster years ago as chief executive of health care giant Columbia/HCA amid a federal fraud investigation. Although Scott was never charged with any wrongdoing, the health care conglomerate paid a then-record $1.7 billion fine for Medicare fraud.

While the Senate contest was one of the marquee races of the U.S. midterm elections, it was shadowed by the governor's race: a bitterly close competition between Republican Ron DeSantis and Democrat Andrew Gillum that became a proxy battle between Trump and his Democratic opponents. Gillum, Florida's first African-American nominee for governor, conceded to DeSantis on Saturday after lagging in a legally required machine recount.

Gary Fineout reports for the Associated Press.