President Donald Trump and Democratic challenger Joe Biden offered sharply different visions of how to handle the surging pandemic and fought over how much Trump pays in taxes during their final debate of a tumultuous campaign.

With Trump trailing and needing to change the campaign's trajectory, the debate could prove pivotal though more than 46 million votes already have been cast and there are fewer undecided voters than at this point in previous election years. The debate did not feature the repeated angry interruptions of the candidates' other showdown, but the men engaged in a series of clashes.

With two weeks until the election's conclusion, the night in Nashville began with a battle over the president's handling of the pandemic, which has killed more than 225,000 Americans and cost millions of jobs. Trump declared that the virus will go away while Biden warned that the nation was heading toward "a dark winter." Polling suggests it is the campaign's defining issue for voters, and Biden declared, "Anyone responsible for that many deaths should not remain president of the United States of America."

WATCH: Post-debate breakdown and analysis

Trump defended his management of the nation's most deadly health crisis in a century, dismissing Biden's warning that the nation had a dire stretch ahead due to spikes in infections. And he promised that a vaccine would be ready in weeks.

"It will go away," said Trump, staying with his optimistic assessment of the pandemic. "We're rounding the turn. We're rounding the corner. It's going away."

"We can't keep this country closed. This is a massive country with a massive economy," Trump said. "There's depression, alcohol, drugs at a level nobody's ever seen before. The cure cannot be worse than the problem itself."

But Biden vowed that his administration would defer to the scientists and said that Trump's divisive approach hindered the nation's response.

"I don't look at this in the way he does--blue states and red states," Biden said. "They're all the United States. And look at all the states that are having a spike in he coronavirus--they're the red states."

Biden said that America has learned from a New York Times report that Trump only paid $750 a year in federal taxes while holding "a secret bank account" in China. The former vice president then noted he's released all of his tax returns going back 22 years and challenged the president to release his returns, saying, "What are you hiding?"

Trump claimed his accountants told him he "prepaid tens of millions of dollars" in taxes. However, as he has for the past four years, after promising to release his taxes, he declined to say when he might do so.

In a visual reminder of the pandemic that has rewritten the norms of American society and fundamentally changed the campaign, sheets of plexiglass had been installed onstage Wednesday between the two men. But in the hours before the debate, they were removed.

The debate, moderated by NBC's Kristen Welker, was a final chance for each man to make his case to a television audience of tens of millions of voters. And questions swirled beforehand as to how Trump, whose hectoring performance at the first debate was viewed by aides as a mistake that turned off viewers, would perform amid a stretch of the campaign in which he has taken angry aim at the news media and unleashed deeply personal attacks on Biden and his adult son.

When he feels cornered, Trump has often lashed out, going as negative as possible. In one stunning moment during the 2016 campaign, in an effort to deflect from the release of the Access Hollywood tape in which he is heard boasting about groping women, Trump held a press conference just before a debate with Hillary Clinton during which he appeared with women who had accused Bill Clinton of sexual assault. He then invited them to watch as audience members.

In a similar move, Trump's campaign held another surprise pre-debate news conference, this time featuring Tony Bobulinski, a man who said he was Hunter Biden's former business partner and made unproven allegations that the vice president's son consulted with his father on China-related business dealings.

Biden declared the discussion about family entanglements "malarkey" and accused Trump of not wanting to talk about the substantive issues.

Turning to the camera and the millions watching at home, he said, "It's not about his family and my family. It's about your family, and your family is hurting badly."

Live Blog: Comments and analysis from News 12's Walt Kane and Tara Rosenblum. 

___

Lemire reported from Washington, Price from Las Vegas. Additional reporting from Steve Peoples in Nashville, Bill Barrow in Atlanta, Alexandra Jaffe, Stephen Braun and Zeke Miller in Washington and Aamer Madhani in Chicago.