A string of recent polls show troubling signs for Donald Trump with older voters, a group central to his reelection effort that appears to be drifting away from him amid a pandemic that has been especially deadly for the elderly.

Former vice president Joe Biden, whose support from older voters helped him lead the primaries, appears to be carrying over some of that appeal into the general election. With Mr Trump seeing sagging approval ratings over his handling of the coronavirus crisis, Mr Biden's campaign is attempting to capitalise with a group that has traditionally leaned towards the Republican party.

In Florida, a Quinnipiac University poll released on Wednesday showed Mr Biden leading Mr Trump by a 10-point margin, 52 to 42, among voters 65 and older - the latest poll showing Mr Trump losing ground with the elderly in key battlegrounds. In 2016, exit polls showed Mr Trump winning seniors in Florida by 17 points over Hillary Clinton, a crucial margin in a state where older voters make up a large percentage of the voting population.

While it's unclear if Mr Biden's polling strength with older voters will carry over into November, the shifts are enough to reshape the dynamics of a close race that has already been upended by a viral pandemic that has killed more than 47,000 Americans.

“We know that Americans over the age of 50 make up the majority of voters - and as a result, they're a deciding factor in our elections,” Nancy LeaMond, American Association of Retired Persons executive vice president and chief advocacy and engagement officer, said in an interview. “They aren't a monolith as a voting bloc, but one thing is clear: They do plan to vote.”

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Ms LeaMond said that while older voters were responsible for Mr Trump's narrow electoral college victory in 2016, their support shifted to Democrats in 2018, helping propel Nancy Pelosi to become speaker of the House of Representatives.

Mr Biden's campaign is trying to replicate the midterm victories. He is relying on a strategy that in many ways mirrors the Democrats' 2018 playbook, which includes focusing on health care and converting suburban, moderate and older voters to his side.

Campaign officials have touted recent polls showing Mr Biden leading Mr Trump in key states such as Pennsylvania, Michigan and North Carolina, including age-based data breaking down his improving numbers with older voters.

Fox News polls released on Wednesday showed Mr Biden ahead 51 per cent to 44 per cent among baby boomers in Pennsylvania, and leading 56 to 38 with members of that cohort in Michigan.

The problematic numbers for Mr Trump come as his handling of the coronavirus crisis has faced withering criticism and low marks from voters, many of whom have told pollsters they do not trust the president to provide accurate information about the pandemic. As Mr Trump pines for the economy to be reopened, most Americans say they fear restarting economic activity too soon, according to a Wall Street Journal/NBC News poll released on Sunday. A resurgence of coronavirus cases would be especially devastating for the elderly.

“They've been scared to death,” said Mr LeaMond, adding that health care is likely to be a top issue for older voters in 2020 just as it was in 2018.

Mr Trump's campaign has dismissed the latest round of polls, in some cases pointing to similar surveys that showed Ms Clinton significantly ahead in key states before the 2016 election.

“Early polls are not good predictors of what will happen on Election Day, and most polls don't screen for likely voters, which is a problem,” said Trump campaign spokesperson Tim Murtaugh. “These polls don't reflect what we see internally.”

After a Biden campaign aide posted a link to the Fox News poll showing Mr Biden ahead of Mr Trump by 8 points in Pennsylvania among registered voters, Trump adviser David Urban took to Twitter to downplay the results.

“Forget how inaccurate 'the polls' were in PA during the 2016 cycle? Not me as I was there!” wrote Mr Urban, who ran Mr Trump's successful Pennsylvania effort in 2016.

Some polls have shown a tighter competition for the elderly vote. A Fox News poll of Florida voters released on Thursday found Mr Biden leading Mr Trump among seniors 46 per cent to 43 per cent.

Mr Biden, who would become the oldest person elected to the presidency, has seen his numbers improve with senior citizens while his campaign has largely been forced into a kind of hibernation by the pandemic. He has recorded remote interviews and podcasts but has not been able to hold rallies or engage in traditional campaigning due to social distancing requirements. Mr Trump, on the other hand, has used his daily televised coronavirus briefings from the White House to tout his efforts and lash out against his opponents, including Mr Biden.

But Mr Trump's approach may be backfiring, as a key component of his base - older voters - is showing some erosion in its support for the president.

“Normally, this is when an incumbent Potus defines (aka, attacks), his challenger,” Amy Walter, national editor of the Cook Political Report, said in a tweet on Thursday. “But, Covid has kept all attention on Trump and none on Biden.”

Even with polls showing Mr Trump with underwater favourability ratings in key states, Ms Walter said in an interview that she expects the race for president remains quite close.

“It feels like everything has changed, and yet there's remarkable consistency,” she said of the race. “It kind of feels like the race that we always knew we were going to have.”

While Mr Trump's national approval ratings have remained in the low- to mid-40s during the pandemic, his numbers have slipped among older voters who are most susceptible to serious health outcomes from contracting the coronavirus.

John Anzalone, a Biden adviser and pollster, pointed to polling he has seen that shows support among seniors for Mr Trump's handling of the coronavirus falling precipitously in recent weeks. He said the movement reflects the real-life impact the pandemic has had on older people.

“This is a universe that's impacted the most on the health and death side of it,” he said. “They think this guy has been unprepared and chaotic and didn't have a plan, and that, quite frankly, that could jeopardize them in a lot of ways.”

Mr Trump has spoken regularly about the need to restart economic activity as quickly as possible, making occasional references to the need to protect the elderly.

“Our Country is starting to OPEN FOR BUSINESS again,” the president tweeted on Wednesday. “Special care is, and always will be, given to our beloved seniors (except me!). Their lives will be better than ever . . . WE LOVE YOU ALL!”

Mr Trump's campaign and allies have concluded that it would be more politically effective to attack Mr Biden than to defend or promote Mr Trump's coronavirus response, The Washington Post reported earlier this month.

In that vein, the president's supporters say Mr Biden's showing with older voters will suffer in the coming weeks and months.

Tim Murtaugh predicted a “dramatic change” in Mr Biden's standing with seniors once Mr Trump's campaign takes steps to highlight less flattering portions of his record, including his recent moves to appeal to more left-leaning voters.

“Remember that Joe Biden only just became president Trump's apparent opponent and we have not yet begun to define him,” Mr Murtaugh said. “Biden has been largely invisible to the public during the coronavirus and once voters get a chance to see him campaigning, they will realise what a disaster he is.”

Brian Walsh, president of America First Action, the main independent political action committee supporting Mr Trump, said he expects television ads hitting Mr Biden on his relationship with China and other issues to reduce his favourability significantly in the coming weeks before the fall election season kicks into gear.

“The one thing we know about Biden is he's a 40-year Washington politician that the American people don't really have any sort of depth of understanding or knowledge of,” he said. “They know who he is. They don't really know what he's done and they don't really have much of an understanding of his past actions or his past decisions.”

Mr Walsh said his group will spend millions of dollars on ads aimed at informing Americans, many of whom are watching more television due to stay-at-home orders, about Mr Biden's record.

Mr Biden's allies have used this time to try to coalesce the party and focus on the singular goal of defeating Mr Trump. They see Mr Biden's dominant performance among older voters during the primaries as evidence that he is best positioned to chip away at Mr Trump's support while also benefiting from the anti-Trump fervour that is energising the party's left-leaning voters.