Joe Biden on Tuesday launched a closing campaign argument that sought to look in part beyond next week’s election, promising in a speech and two campaign ads to heal the nation and bring it together as he evoked the memory of Franklin D. Roosevelt and drew mostly implicit contrasts with President Trump.

Trump, in contrast, intensified his focus on his adversaries, challenging any mail-in ballots received after Election Day, suggesting the pandemic has been overstated and taking aim at two powerful Democrats, vice-presidential nominee Kamala D. Harris and Michigan Gov. Gretchen Whitmer.

The contrasting messages, one week before Election Day, crystallized the vastly different lenses through which the candidates see the race. Biden, ahead in the polls, is seeking to motivate supporters by painting a post-Trump America in increasingly vivid terms. Trump is playing down the pandemic and raising unfounded concerns about the vote, seeking to energize his base and set the stage for a potential challenge to the election results.

Former president Barack Obama, meanwhile, has emerged as Biden’s most aggressive surrogate, saying Tuesday in Florida that Trump had given up on fighting the pandemic and mocking the president for complaining about his treatment by the news media.

Biden made his comments in his first campaign stop in Georgia as the Democratic nominee, a mark of how the field appears to be tipping in his favor. Polls show a close race in the state, which a Democratic presidential candidate has not won since 1992. In his second stop, a drive-in rally meant to energize voters in Atlanta, he resumed his more aggressive attacks on Trump.

Speaking in Warm Springs, Biden quoted Roosevelt — who, as a polio survivor, regularly visited the town for therapy — as he decried the swirl of crises confronting the nation and vowed to address them swiftly as president.

“With our voices and our votes, we must free ourselves from the forces of darkness, from the forces of division, and the forces of yesterday,” Biden said.

In some of his sharpest language yet, Biden cast a spotlight on recent police killings of unarmed African Americans. He named George Floyd, Breonna Taylor and Jacob Blake, Black Americans who either were killed or wounded by police this year, saying they would “inspire a new wave of justice in America.”

“A season of protest has broken out all across the nation. Some of it is just senseless burning and looting and violence that can’t be tolerated — and won’t,” Biden said. “But much of it is a cry for justice from a community that’s long had a knee of injustice on their neck.”

Biden has sometimes struggled to balance an embrace of racial-justice demonstrations with his criticism of violence and looting. On Tuesday, Biden and Harris issued a statement denouncing the fatal police shooting of Walter Wallace Jr. in Philadelphia on Monday, while also calling for an end to the violence and looting that occurred during some of the ensuing protests. Trump on Tuesday aligned himself with law enforcement and claimed that Biden “stands with the rioters,” even as the Democrat has repeatedly stated he does not.

Democrats hope to spring an upset in Georgia thanks in part to large turnout among African American voters. Later Tuesday, Biden spoke in Atlanta, where he took note of the race’s closeness, as some polls suggest he and Trump are essentially tied in the traditionally Republican state.

Biden spoke at a “car rally,” and some of the loudest applause and honking came when he drew a contrast with Trump on the issue of race. “He won’t say, ‘Black lives matter,’ because they do. We know they matter,” said Biden. He also slammed Sen. David Perdue (R-Ga.) for mockingly mispronouncing Harris’s name in recent comments that many of her supporters saw as racist. “It’s gotta stop,” Biden said.

At Trump’s three campaign events Tuesday, the president had a sharply different message. Speaking of widespread virus testing before a crowd in Lansing, Mich., Trump remarked, “In many ways, I hate it.” He blamed the current surge in case numbers on the broader availability of testing, though hospitalizations also have been rising.

The virus was not the only issue on which Trump’s words were at odds with the truth. As he left the White House to hit the campaign trail, Trump told reporters, “It would be very, very proper and very nice if a winner were declared on Nov. 3 instead of counting ballots for two weeks, which is totally inappropriate, and I don’t believe that that’s [allowed] by our laws.”

While some states count only ballots that arrive by Election Day, others count those that are postmarked by Election Day and arrive within a specified time. The issue of whether extensions should be granted because of the pandemic has been a focus of multiple lawsuits, including two that have reached the Supreme Court.

Millions of Americans have already voted, all but ensuring that the majority of ballots will have been cast before Election Day for the first time in the country’s history. Democrats appear to be voting early in larger numbers, but there are signs that the rate of Republican early voting is increasing.

Trump continued his heavy campaign schedule with rallies set for Wisconsin and Omaha later Tuesday. Biden has kept up a more limited travel schedule — a factor Trump mocked Tuesday.

“This ‘Sleepy Joe’ — the guy goes to his basement,” Trump said.

An enthusiastic crowd stood close together outdoors in a steady rain in Michigan as Trump introduced a video featuring past Biden statements about China, the North American Free Trade Agreement and fracking. Biden does not oppose fracking but has muddled his position at times, giving Trump and his allies an opening in states such as Pennsylvania.

Trump also suggested that Biden is mentally weak and that Harris, a senator from California who is more liberal, would take power early in a Biden presidency. “Three weeks in, Joe’s shot — let’s go, Kamala, you ready?” he said.

Biden sought to complement his pitch on the campaign trail with a pair of new ads, neither of which explicitly mentions Trump or a specific policy issue. Instead, they aim to leave voters with a positive personal impression of the Democratic nominee and return to the themes with which he launched his campaign last year.

“I started this campaign saying we were in the battle for the soul of the nation. I believe that even more deeply today,” Biden says in one of the ads, speaking directly to the camera. In a second ad, his wife, Jill Biden, speaks about the personal tragedies he has overcome and concludes that he will do for hurting American families “what he did for ours — bring us together.”

Biden centered his speech in Warm Springs on the theme of healing, drawing a parallel to Roosevelt and speaking of the “pre-vaccine decades” in which the former president lived.

“To him and to so many others facing physical challenges, Warm Springs offered therapy for the body, and I might add, and the soul,” he said. “FDR came looking for a cure, but it was the lessons he learned here that he used to lift a nation.”

Biden said he, too, was prepared to meet monumental challenges facing the country. “I’m ready to act. I know what to do. And starting on Day One of my presidency, we will do it,” he said.

With a sea of fog and pine trees behind him, Biden spoke at the Mountain Top Inn and Resort, a getaway filled with log cabins in the hills of the Georgia Piedmont.

He encouraged his audience to imagine how different things would be if Trump had promoted mask use and social distancing. He concluded by urging Americans to “stay safe and wear your masks,” putting his own mask back on as he exited.

As the candidates hit the trail, their surrogates did as well. Rep. Mike Kelly (R-Pa.), a Trump supporter, appeared to mock Biden’s stutter and his age. At 78, Biden would be the oldest president ever sworn in if he wins.

“He’s been against fracking since the beginning of this primary season,” Kelly said. “He’s pledged that he would eliminate — he kind of stumbled — ‘I-I — we-we-we, we’ll work it out, we’ll work it out, we’ll work it out,’ ” Kelly said.

Biden grew up with a stutter. He often talks about his experience with bullying and told the Atlantic’s John Hendrickson this year about a nun who called him “Mr. Buh-Buh-Buh-Biden” in front of his seventh-grade class.

A Biden spokesman did not immediately respond to a request for a response to the attacks from Trump and Kelly.

But Obama was more than willing to go after the president, speaking with an acidity rarely seen from former presidents.

“Our current president, he whines that ‘60 Minutes’ is too tough,” Obama said, referring to Trump’s recent interview with the CBS News program. “You think he’s going to stand up to dictators? He thinks Lesley Stahl’s a bully.”

Obama noted that “just yesterday, he said that the leaders of North Korea want him to win.”

“We know!” Obama continued, to laughter from the crowd. “We know, because you’ve been giving them whatever they want for the last four years. Of course they want you to win! That’s not a good thing.”

John Wagner, Paulina Firozi and Colby Itkowitz in Washington and Haisten Willis in Warm Springs, Ga., contributed to this report.