Democratic White House challenger Joe Biden blasted President Donald Trump as a conman during a campaign foray into traditionally Republican territory.
In Georgia, Mr Biden said that Mr Trump’s handling of coronavirus amounted to a “capitulation”.
Mr Trump kept blitzing the swing states that he won in 2016, warning in Michigan that its “economic survival” was on the line if Mr Biden won.
According to opinion polls, Mr Trump lags behind with a week to go.
But the race is tighter in critical battleground states such as Arizona, Florida and North Carolina.
More than 69 million people have already voted early by post or in person in a record-breaking surge driven mainly by the coronavirus pandemic.