He accused Democrats of being "driven by prejudice, hatred, and rage" (a charge frequently leveled at the president himself) while supporters revived chants of "Lock her up!" and "Drain the swamp!" and "CNN sucks!"
His second term plans to fight AIDS, put a man on Mars, and protect Second Amendment rights came at the end and without detail.
Hours before Trump's rally, Quinnipiac University released a poll showing that in Florida, another critical swing state, voters give Trump a negative approval rating, 51% to 44 percent, and that the president would trail the top Democratic contenders there.
Others polls have found similar results in Pennsylvania and other battleground states, and have been backed up by some of the Trump campaign's internal polling numbers that were leaked to reporters.
Trump and Republicans argue, however, that he is far better positioned to win this time.
Unlike the haphazard 2016 campaign, Trump has a fully staffed operation working for him from a sleek Arlington, Va., office. His campaign has already spent more than $10 million on digital ads on Facebook and Google, dwarfing every Democratic contender, according to tracking by Bully Pulpit Interactive, a Democratic consulting firm.
His team is collecting data from the thousands who attend Trump rallies, hoping to organize a volunteer army. And the president has an emotional pull on his supporters that few politicians can match.
People began lining up outside the Amway Center in Orlando more than 40 hours before Trump's rally. Elsewhere, the Republican National Committee planned about 1,000 watch parties across the country, including 37 in Pennsylvania.
"We were an insurgent campaign last time," said Ted Christian, Trump's 2016 state director in Pennsylvania, "Now we have almost an 18-month head start on the reelection. It's nice to have a unified party, and I think everyone is very excited about working for the president and touting his accomplishments."
Trump fans at a watch party at Conshohocken Brewing Co. in King of Prussia wore Make America Great Again hats and lots of red. Dasha Pruett, who came to this country from Russia when she was 10, said she sees the president as a shield against socialist-leaning Democratic candidates.