Melania Trump has cancelled a planned campaign appearance due to a lingering 'Covid cough'.

The First Lady was due to accompany President Donald Trump to a rally in Eyrie, Pennsylvania tonight.

It was to be her first public appearance since being diagnosed with Covid-19, three weeks ago.

And it would have been her first campaign trip with her husband since the Republican National Convention in August.

The first lady's Chief of Staff, Stephanie Grisham said the First Lady had decided not to go on the trip out of an abundance of caution.

With more than 33 million early ballots already cast two weeks before voting ends on Election Day Nov. 3, time is running short in his contest against Democratic challenger Joe Biden.

National polls show former Vice President Biden holding a wide lead on Republican Trump, though the contest is closer in swing states that decide elections including Florida, North Carolina and Pennsylvania.

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Image:
AFP via Getty Images)

Trump has gained some ground on Biden in Pennsylvania, according to a Reuters/Ipsos poll released on Monday, which showed the challenger leading by 49% to 45%, slightly narrower than a week earlier.

Trump's handling of the coronavirus pandemic, which has killed more than 220,000 people in the United States and thrown millions out of work, has taken a toll on his re-election prospects.

Despite rising cases of the highly contagious disease, which landed Trump in hospital for three nights, he has resumed a heavy schedule of campaign travel including rallies where his supporters pack together tightly, many not wearing masks.

Trump persists in calling for an end to social restrictions that medical experts say limit the spread of infection and for the country to reopen for business. On Monday he lashed out at top infectious disease expert Dr. Anthony Fauci, calling the highly respected figure a "disaster."

Trump's path to victory is narrowing in the state-by-state race that determines who will move into the White House on 20 January next year.

Reuters/Ipsos polling shows Trump trailing in Wisconsin and Michigan, the two other Rust Belt states that he narrowly carried four years ago. Trump also trails in Arizona and the two are effectively tied in Florida and North Carolina.

More than 33.3 million votes have been cast, according to the University of Florida's U.S. Elections Project, more than a fifth of the total vote in the last presidential contest four years ago.

Early returns show registered Democrats outpacing Republicans in most states that track party affiliation. Trump has repeatedly characterized absentee voting as unreliable, though experts say it is as secure as any other method.

His campaign and the Republican Party have sought, with mixed success, to limit voting by mail in states that expanded it in response to fears of spreading COVID-19 at crowded polling places.

In Pennsylvania, his campaign has failed to prevent officials from setting up ballot drop boxes, a popular option in many other states.