U.S. Sen. Nelson concedes to Florida Gov. Scott

Democratic Sen. Bill Nelson has ended his bitterly close re-election bid by conceding the race to Republican Rick Scott. 

Nelson gave up the fight Sunday to Florida's outgoing governor on a day when Florida's counties had to submit their official results. Those results showed that the three-term incumbent trailed Scott by more than 10,000 votes.

"I was not victorious in this race, Nelson said in taped remarks. "Things turned out a little differently than we had hoped, but I by no means feel defeated."

Nelson's concession capped tumultuous days of recounting and political tension in the perennial presidential swing state. It also will likely end the long-running political career of the 76-year-old Nelson. He was first elected to Congress nearly 40 years ago and then to the Senate in 2000. 

"To all Floridians, whether you voted for me, or for my opponent, or you didn’t vote at all, I ask that you to never give up this fight," Nelson urged.

Nelson and Democrats had filed several lawsuits over the recount, but a federal judge rejected most of them.

Florida will not officially certify the final totals until Tuesday.