WASHINGTON — President Donald Trump's coronavirus diagnosis has been an earthquake for his campaign, leaving some Republicans to worry that the election is slipping away.
The president's wishful assertions that the virus would disappear have been shattered. If it wasn't clear enough, it is now: The election will be about the coronavirus.
Trump's iconic campaign rallies are canceled, depriving him of some of his best chances to recruit new supporters and excite his old ones, while placing a brighter spotlight on his history of rarely wearing masks and downplaying the severity of the virus.

As the president was admitted to a hospital for treatment Friday, his Democratic rival, Joe Biden, who his physician said had tested negative and whom the president had mocked for campaigning virtually, spent the day shoring up support in person in the battleground state of Michigan.
The September jobs report released Friday — the last to be released before Election Day on Nov. 3 — revealed signs of a sputtering recovery just as Trump was counting on the improving economy to propel him to another four years.
Although he has an advantage among voters over Biden in who would best handle the economy, surveys indicate that the country trusts Biden president by wide margins on managing the coronavirus and the health care system. The president's infection adds new scrutiny to his management of the virus, which has been his political Achilles' heel.
"This does put the focus squarely on the health care side of Covid and not the economic side, which the president and his campaign wanted to focus on," said Republican consultant Matt Gorman, a top aide for the party's House campaign arm in 2018.
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Trump already had an uphill climb, trailing Biden by 7 to 8 percentage points nationally, according to the NBC News polling average, and he was behind in most swing states. The first debate Tuesday appeared to do little to help him, and the next two debates could be up in the air as Trump battles Covid-19.
Voting is already underway, with many Americans casting ballots early in person or by mail. The president has little time to make up a lot of ground.
Trump supporters acknowledge the peril but aren't ready to give up.
"This is a nightmare scenario for Donald Trump," said Dan Eberhart, a major Republican donor. "But he's a gladiator and can carry the stress of mountains on his back. I wouldn't count him out."
Trump's management of the virus has come under a new microscope after a swath of people said they had tested positive for Covid-19 after having attended a ceremony on Sept. 26 announcing the nomination of federal appeals Judge Amy Coney Barrett to the Supreme Court. They include two Republican senators on the Judiciary Committee — Mike Lee of Utah and Thom Tillis of North Carolina — with others being tested after having attended what some fear may have been a virus "superspreader" event.
The new infections could slow the political momentum behind Barrett's nomination, which Trump had hoped would rouse conservatives in the final weeks before Election Day. Senate Republican leaders say they're determined to proceed with the committee hearing for Barrett on Oct. 12 — virtually if need be — although Senate rules say they'll need to be physically present to vote.
In Grand Rapids, Michigan, on Friday, Biden offered his prayers "for the health and safety of the first lady and president of the United States after they tested positive for Covid-19."
"This is not a matter of politics. It's a bracing reminder to all of us that we have to take this virus seriously. It's not going away automatically," he said. "We have to do our part to be responsible. It means following the science, listening to the experts, washing our hands, social distancing. It means wearing a mask in public and means encouraging others to do so, as well."
And Biden hit Trump on his economic record, raising alarms about the sharp drop in women's participation in the labor force. "This will be the first presidency in modern history to leave office with fewer jobs than when it came into office," he said.
Trump campaign manager Bill Stepien announced the suspension Friday of all campaign events involving Trump's participation, but he said, "Vice President Mike Pence, who has tested negative for Covid-19, plans on resuming his scheduled campaign events."

