President Donald Trump and Democratic challenger Joe Biden squared off Tuesday night in their crucial first debate of the 2020 campaign, the most pivotal opportunity yet for them to outline starkly different visions for a country facing multiple crises.

Trump and Biden arrived in Cleveland hoping the debate would energize their bases of support, even as they competed for the slim slice of undecided voters who could decide the election. It has been generations since two men asked to lead a nation facing such tumult, with Americans both fearful and impatient about the coronavirus pandemic that has killed more than 200,000 of their fellow citizens and cost millions of jobs.

With just 35 days until the election, and early voting already underway in some states, Biden stepped onto the stage holding leads in the polls — significant in national surveys, close in some battleground states — and looking to expand his support among suburban voters, women and seniors. Surveys show the president has lost significant ground among those groups since 2016, but Biden faces his own questions encouraged by Trump’s withering attacks.

Trump had arguably his best chance to try to reframe the campaign as a choice between candidates and not a referendum over his handling of the virus that has killed more people in America than any other nation. Americans, according to polling, have soured on his leadership in the crisis, and the president has struggled to land consistent attacks on Biden.

Leaving the White House for Cleveland, Trump pumped his fist for supporters gathered on the White House lawn but did not address reporters. He spent the morning in informal debate preparations while a more formal session was set for the afternoon once he arrived in Ohio. Biden held an umbrella to ward off the Delaware rain as he boarded a new, bigger campaign plane en route to Cleveland. He, too, did not address reporters.

Though some Trump aides involved in the preparations urged the president to adopt a measured tone while selling his own accomplishments, Trump had told advisers he was preparing an all-out assault on Biden, claiming that the former senator’s 47 years in Washington have left him out of touch and that his family, namely his son Hunter, has benefited from corruption.

Biden’s performances during the primary debates were uneven, and some Democrats have been nervous as to how he would fare in an unscripted setting. But his team also viewed the night as a chance to illuminate Trump’s failings with the pandemic and economy, with the former vice president acting as a “fact checker on the floor” while bracing himself for the onslaught that was coming.

The tumult of 2020 was difficult to overstate: Covid-19 has rewritten the rules of everyday life; racial justice protests have swept into cities after several highly publicized killings of Black people by police, and the death of Supreme Court Justice Ruth Bader Ginsburg allowed Trump to nominate a conservative jurist to replace a liberal voice and perhaps reshape the high court for generations.

But the impact of the debate — and the two to follow — remained unclear. Despite the upheaval, the presidential race has seemed largely unchanged since Biden seized control of the Democratic field in March and opened a steady lead over Trump.

Both sides looked to one-up each other in the hours before the debate.

Biden released his 2019 tax returns just days after the blockbuster revelations about Trump’s long-hidden tax history, including that he paid only $750 a year in federal income taxes in 2016 and 2017 and nothing in many other years. The Bidens paid nearly $300,000 in taxes in 2019.

Meanwhile, trying to hammer home a claim that Biden is not up to the job of president, Trump’s campaign pushed out a number of pre-debate accusations, including that the former vice president asked for numerous breaks during the 90-minute debate and had backed out of a search meant to rule out that either man was wearing an earpiece from which he could be fed answers.

The Biden campaign denied the accusations and, in a conference call Tuesday afternoon, chided reporters for biting on a Trump gambit.

“We’re in the middle of a global pandemic,” Biden senior campaign adviser Symone Sanders said. “Is this what you all would really like to spend your time on, these false, crazy, random, ridiculous assertions by the Trump campaign?”

The president’s handling of the coronavirus was likely to dominate much of the debate. The pandemic’s effects were in plain sight, with the candidates’ lecterns spaced far apart, all of the guests in the small crowd tested and the traditional opening handshake scrapped.

The scene in Cleveland was notably understated compared to typical election years, with none of the pomp and pageantry. Instead of the usual auditorium, the debate was held in an atrium on Case Western University’s campus — one that had been temporarily converted into a Covid-19 hospital this spring — and signs were placed on two of every three three chairs reading, “Thank you for not sitting here in observance of social distancing.”