St. Petersburg, Florida (CNN) John Dudley, a retired banker, proudly cast his ballot for Donald Trump in 2016, excited at the prospect of sending an entrepreneur to the White House on a pledge to change Washington.
It's a vote he regrets, he said, and a mistake he hopes to correct in November.
"He blew it," Dudley said, not mincing words as he assessed Trump's first term. "We were so excited in the beginning. A businessman to run our country like a business and it hasn't happened."
The searing sentiment of Dudley, 77, illustrates one of the rising worries inside the Trump campaign: losing the senior vote, a reliably Republican constituency for two decades.
Here in Florida, people 65 and older made up 21% of the vote in 2016. Trump won that group by 17 points over Hillary Clinton. But now, one poll after another shows Joe Biden either tied -- or with an edge -- among senior citizens in key battleground states and nationally.
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"We've got to get a new guy. Our President is erratic," said Dudley, who has largely voted Republican for nearly six decades. "All he's succeeded in doing is juicing up the stock market. Now that's gone to pot because of the coronavirus."
The worries over losing the senior vote come as coronavirus cases climb nationwide, four months before the general election. And here in Florida, summertime signs of anxiety are plentiful, as another record-setting 11,445 new cases were reported Saturday.
The administration's handling of the crisis was raised again and again during interviews with older voters -- a group more vulnerable to serious illness from coronavirus -- here this week. Several people pointed to the pandemic as only their latest disappointment of the Trump presidency, with some using words like "embarrassment" and "laughing stock to the world" to describe their view of the President.
"I hoped that I would be wrong in not voting for him and that he would turn out to be a great president, but it didn't happen," said Marsha Lundh, 77, a Michigan retiree living here and a lifelong Republican who plans to vote for Biden in November.
She said that defeating Trump would add stability to the country and the world.
"We're very divided in every way," she said. "Everything could have been handled better and should have been handled better. Now is a chance to change things."
Paula Schelling left the Republican Party because of Trump, after voting for GOP candidates for much of her life. She changed her registration to "no party affiliation" and also plans to vote for Biden.
"I had to change parties. I could not do this anymore," said Schelling, 74, a retired teacher. "As I saw his interactions with foreign countries, how they were laughing at us, it just fortified my thoughts."
For Trump, there is virtually no path to reelection without winning Florida, a state where seniors have outsized influence. The key battleground states of Arizona, Michigan, Pennsylvania and Wisconsin also have large elderly populations, which has top Republicans sounding the alarm about the erosion of support among older voters.
"It wasn't going to be easy anyway, but coronavirus has turned this into a perfect storm," a senior Republican told CNN, speaking on condition of anonymity to discuss growing concern over the prospect of losing a significant share of older voters. "We can't win if we lose seniors."
The fight for the critical senior vote is playing out as a contest among peers, with Trump, 74, and Biden, 77, steadily escalating their campaigns against one another. Trump is working to increase his support among older white men, a crucial part of his base, while Biden is trying to expand his appeal among older white women. Voters of color strongly favor Biden, polls show.
On Florida's Gulf Coast, Trump won Pinellas County by 1 percentage point -- the same margin he carried the state. Democrats and Republicans had roughly the same number of registered voters in 2016, but Democrats have an advantage of about 10,000 now, which make places like the "On Top of the World" retirement community a hot campaign battleground.
"There are more Democrats now than there used to be in years past," said Donna Lukas, a longtime leader of the community's Democratic club. "People seemed to have a hatred of Hillary for a variety of reasons, but I'm not hearing as much negativity about Joe. I know some Republicans who are definitely not voting for Trump and are probably going to vote for Biden."
David Cordes, the newly elected leader of the Democratic club, said that he "wasn't wild about Hillary, but I was absolutely against Donald Trump." He said he talks to many people who will enthusiastically support Biden.
"I know several," Cordes said, "including my son and grandson."
Inside this sprawling condominium community of about 10,000 retirees, which is large enough to require two voting precincts, several Democrats repeated the same sentiment. Only in November will it become clear whether the anecdotal evidence is proven at the polls -- or through absentee voting, which also could be central to the scope of turnout this fall, with vote-by-mail requests rising amid the coronavirus crisis.
Robert Blethen, a loyal Trump supporter in the community who believes he will win a second term, said he wished the President would do one thing: wear a mask.
"He is our leader. We look up to him," Blethen said. "Our President should wear a mask."
The airwaves are filled with political ads here in Florida, including a Trump campaign commercial that questions Biden's fitness for office. That spot did not sit well with Democrats here like Joyce Monahan, a retired professor.
"Trump is not that much younger, but in the case of Joe Biden, his inherent wisdom and his desire to surround himself with the best people is clear. He's already said Anthony Fauci is coming with him," she said with an air of excitement in her voice. "This is the wrong place to talk about age!"
While many Democrats expressed an upbeat mood at Biden's standing in the polls and how the party appears to have unified behind his candidacy, a sense of unease was also clear.
"What I worry about the most is the Republicans not wanting Trump, but who don't vote for Joe," said Dianna Wade, 64, as she played a game of shuffleboard at an outdoor park here the other night. "That's just a vote for Trump as far as I'm concerned. If they want him out, they've got to vote for Joe."
Jim Donelon, president of the Democratic Club of St. Petersburg, said he cannot recall another election in his lifetime when he felt as much enthusiasm among Democrats. Much of it, he said, springs from a disgust for the President and a demand for change.
"Trump is our biggest ally, as far as I'm concerned," said Donelon, 77. "He's turning out people who have never been interested in politics before."
This story has been updated with Saturday's tally of new cases of coronavirus in Florida.