The ceremony took place Monday and was overseen by Secretary of State Ken Detzner. The electors were selected by the Republican Party of Florida.
Protesters shouted, "Love trumps hate" just before the vote took place, and "Vote your conscience" as the electors filled out their ballots.
Nick DiCeglie is head of the Pinellas County GOP, and one of the state's 29 electors. He called the process "humbling," "intimate" and above all, "reverent."
"There was a point during the process where you could literally hear a pin drop in the chamber," he said."So the electors took it very seriously, the folks in the gallery took the process seriously and I mean it was just an amazing experience."
He's gotten thousands of emails and letters, with most of them focused on the fact that Hillary Clinton won the popular vote. Still, every one of the electors cast their ballot for Trump.
"We represent the will of the people," DiCeglie said. "And when you're in those chambers, ready to execute that responsibility and that duty, it's just an amazing, amazing experience that's such an honor."
Earlier, protesters gathered outside the state's historic old Capitol and waved signs at drivers before moving inside the current Capitol. Among them was Randie Denker, a 66-year-old lawyer who said Trump is unfit to be president.
Denker said Trump is an embarrassment to the country, has already alienated China and has conflicts of interest with his foreign businesses.
Despite their efforts, Trump will be inaugurated on the steps of the U.S. Capitol on Jan. 20th.