Democrat Joe Biden insisted Wednesday he will tackle coronavirus from Day 1 if elected president but warned there is no magic "switch" to end the pandemic, as Donald Trump insisted he will still win easily and dismissed his opponent as a COVID-19 alarmist.
Less than a week before decision day, Biden cast his presidential ballot in his home state of Delaware and met with health experts, as he fine-tuned his pandemic response plan, seeking to reassure voters that he would use science to fight the contagion.
"Even if I win it's going to take a lot of hard work to end this pandemic," the former vice president, who has a strong lead in opinion polls, said in Wilmington.
"I'm not running on a false promise of being able to end this pandemic by flipping a switch," he added. "But what I can promise you is this: We'll start on Day 1 by doing the right thing. We'll let science guide our decisions."
Biden, 77, continues to campaign cautiously ahead of next Tuesday, holding low-key events with small, socially distanced crowds that look nothing like the traditional scene in the closing days of a White House race.
On Saturday, Biden is to get some star power when he's joined on the stump in Michigan by Barack Obama, whom he served as vice president. It will be their first joint in-person appearance of the 2020 race, though Obama has been delivering strategically timed broadsides at Trump throughout.
Trump, by contrast, is finishing his campaign in an extreme test of endurance, with a final attempt to catch up both in swing states and also states that he won in 2016 yet now has to defend.
After rallying supporters in three states Tuesday, Trump, 74, overnighted in a fourth - Nevada - then flew to Arizona for two more rallies.
On an airport tarmac in Bullhead City, Trump all but ignored the COVID-19 crisis and many supporters didn't bother with masks as they cheered his defiant insistence on a landslide victory November 3, despite all the bad polls.
"It's going to be a great, great red wave," he boomed, referring to the Republican color.
"We love you! We love you!" the enthusiastic crowd chanted back.
At another rally, in Goodyear, Arizona, Trump predicted he'd repeat his 2016 upset, saying "we're going to have an even bigger surprise in six days."
"The only thing I worry about is if they cheat with the ballots," he said, talking at length about his latest conspiracy theory that the US polls could be rigged - yet, as always, providing no evidence.
The pandemic has upended all aspects of American life and overshadowed the election, with polls showing it may well be the president's undoing as cases hit record levels in the US.
With many Americans fearing the risk of voting in crowded polling stations, a remarkable 74.7 million people have already cast their ballots.
Some 57.4 percent of Americans disapprove of Trump's coronavirus response, while 39.8 percent approve, according to a poll average compiled by tracker FiveThirtyEight.com.
Biden has seized on that to build an impressive advantage in polls heading into the final week and looking to expand his state-by-state path to victory.
On Tuesday, Biden visited Georgia, traditionally Republican territory, and he has said he would travel to Florida, Wisconsin and Michigan in the race's closing days.
All are states that Trump won in 2016 but which are up for grabs this year.
Trump has repeatedly stressed that the US is "rounding the turn" on the pandemic, but figures do not bear that out: More than 227,000 Americans have died and daily case averages have risen.
On Wednesday, Trump kept up his scorn for Biden's focus on health safety, saying that the Democrat would destroy the country through more lockdowns.
"'Sleepy Joe' wants to keep everyone locked down forever," he said, using his stock insult for his challenger.
"If you vote for Biden it means no kids in school, no graduation, no Christmas and no Fourth of July together. Other than that you'll have a wonderful life."
But Trump's own chief infectious disease specialist, Anthony Fauci, warned Wednesday that evne if a Covid-19 vaccine is released this year, it will take to "the end of 2021 and perhaps even into the next year" to reach "some semblances of normality."
Biden blasted the president, calling his administration's response to the pandemic "an insult to every single person suffering from Covid-19 and every family who's lost a loved one."
With American and European Covid-19 cases rising and no agreement yet on a new US pandemic rescue package in Congress, the Dow Jones on Wednesday sank three percent by early afternoon, its fourth straight session of losses.
The White House said meanwhile that it was closely following the situation in Philadelphia, where a second straight night of unrest and looting set the city on edge following the fatal police shooting of a Black man, the latest to spark anger in the United States.