Donald Trump and Joe Biden have been travelling across the nation as the US election enters its closing stage.
President Trump visited five battleground states while his challenger Mr Biden spoke at a campaign event in Pennsylvania.
The Democratic candidate maintains a solid national lead in the polls ahead of Tuesday’s general election.
But this advantage is narrower in key states which could decide the result.
More than 90 million people have already cast their ballots in early voting, putting the country on course for its highest turnout in a century.
The election comes amid the ongoing coronavirus pandemic. The US has recorded more cases and more deaths than any other country worldwide, reporting more than 99,000 infections on Saturday alone.
Top virus expert Anthony Fauci has sharply criticised the Trump administration’s handling of the pandemic, drawing a rebuke from the White House on Sunday.
The Republican president had a punishing schedule on Sunday, holding rallies in Iowa, Michigan, North Carolina and Georgia, followed later by Florida – all states where polls suggest a tighter race.
Speaking in Washington, a town in Michigan north of Detroit, Mr Trump told his supporters that under his leadership “the economy is now growing at the fastest rate ever recorded”.