On Friday, President Donald Trump campaigned in Fort Myers, Florida, a state with one of the highest populations of elderly voters, delivering remarks aimed at reassuring older Americans that he will protect them from the pandemic.

"I am honored to be here in Fort Myers to reaffirm my solemn pledge to America's seniors," Trump said. "I will protect you, I will defend you, and I will fight for you with every ounce of energy and conviction that I have."

Trump delivered his speech in front of an indoor crowd, some of them not socially distanced and many not wearing masks.

"My message to American seniors today is one of optimism, confidence and hope," Trump said, adding that "the light at the end of the tunnel is near, we are rounding the turn" on the pandemic.

Adults age 65 and older make up 23% of the 2020 American electorate, the highest share since at least 1970. Trump won this group by 9 percentage points in 2016, but latest polls show that Democratic nominee Joe Biden is leading by a significant margin.

A recent survey by NBC and the Wall Street Journal shows that 62% of respondents 65 and older back Biden compared with 35% who support Trump.

The president is losing seniors in many states, often by very substantial margins, said Whit Ayres of North Star Research. The Republican strategist attributed this to the president's downplaying of COVID-19, a pandemic that older people are most vulnerable to.

Protecting older Americans

Adults 65 and older make up 16% of the U.S. population but account for 80% of COVID-19-related deaths in the country, a fact that Trump acknowledged in his remarks.

"As president, I am deeply aware that America's 54 million seniors have borne the heaviest burden of the China Virus," he said.

Biden has sought to make the election a referendum on Trump's handling of the pandemic, arguing that the administration's mismanagement has cost Americans lives, particularly seniors. Earlier this week, Biden traveled to a senior center in Pembroke Pines, Florida, to push the message that the president has neglected older Americans.

"To Donald Trump, it's simple - not a joke - you're expendable. You're forgettable. You're virtually nobody," Biden said. "That's how he sees seniors. That's how he sees you."

On Friday, Trump repeated his promise to "deliver life-saving therapies in record time, and to distribute a safe and effective vaccine before the end of the year."

"Seniors will be the first in line for the vaccine, and we will soon be ending this pandemic," he vowed.

Trump said the Food and Drug Administration and Health and Human Services are working to make the antibody treatment from Regeneron Pharmaceuticals - the drugs that he received after his own COVID-19 diagnosis - available "to everyone who needs it for free."

Trump's statement repeats the claim he made in a video he tweeted days after his release from the hospital earlier this month, promising seniors the same treatment he received from his doctors, including the experimental drug currently undergoing clinical trials.

Trump was diagnosed with COVID-19 Oct. 2 and spent three days at Walter Reed National Military Medical Center. His campaign has tried to frame his illness as an electoral asset, claiming the president has firsthand experience dealing with the coronavirus that Biden lacks.

But a new AP-NORC poll finds just 26% of Americans approve of the way the administration handled Trump's diagnosis, while 54% disapprove. About 8 in 10 Democrats and 2 in 10 Republicans disapprove.

"His diagnosis, his quick recovery after world-class medical care, and him talking about himself like Superman and saying the diagnosis was a blessing from God, probably does not sit very well among most Americans," said Republican strategist Whit Ayres.

No longer the moderate

While the pandemic is one factor in Trump's losing ground, seniors' support for the president has slipped since mid-2019. One possible reason is that Trump is no longer seen as the moderate candidate in 2020 as he was in 2016, said Robert Griffin, research director for the Democracy Fund Voter Study Group.

"When we asked people who they perceive as moderate, Donald Trump scored much higher on this among seniors than did Hillary Clinton," Griffin said of the 2016 race.

"Donald Trump is far less likely to be considered moderate today," Griffin said, adding that more moderate candidates tend to get higher shares of votes, particularly among seniors who themselves are a more moderate portion of the electorate.

In Florida, the 74-year-old Trump renewed attacks on his opponent, who is 77, again calling him "Sleepy Joe." He recently tweeted a photoshopped meme of Biden in a wheelchair surrounded by seniors.

"Trump has doubled down on the idea that Joe Biden isn't functioning well anymore, simply that he is too old, implying with no evidence that he has dementia," said Chris Cooper, a professor of political science at Western Carolina University. "It doesn't play very well with a senior audience."

Meanwhile, the Trump campaign this week launched ads targeting senior voters in key battleground states. The ads argue that the president has lowered the cost of drugs and protected Social Security and Medicare, federal government programs that help seniors.