Florida's Democratic Party has declared victory for President Barack Obama in the closely divided battleground state.
The chairman of the state's Democratic Party, Rod Smith, congratulated Mr Obama on winning Florida's 29 electoral votes.
In a tacit concession, Republican Party of Florida spokesman Brian Burgess said in an email that he and other Romney supporters were "obviously not happy with the result."
As of early Thursday evening, Obama had 49.92% of the statewide vote versus 49.22% for Romney, according to the Florida Division of Elections.
Three of the 67 counties were still being tallied. Two are heavily Democratic and the third, though having more registered Democrats than Republicans, has traditionally leaned Republican in presidential contests.
Just 58,100 votes separated the two candidates, but that was far more than in 2000, when George W. Bush won Florida by 537 votes and captured the White House.
This time, however, Mr Obama had already won re-election without its 29 electoral college votes - the biggest prize of any of the nine key US swing states.
If Mr Obama wins Florida, it will add to his electoral college margin and he will have won all of the key US swing states.