Democrats jumped on the allegations, with House Speaker Nancy Pelosi saying it showed "Trump's disdain for America's working families", and party colleague Chuck Schumer calling for everyone "who paid more in federal income tax" to raise their hand.
Massachusetts representative Richard Neal, the chair of the House Ways and Means Committee who has tried unsuccessfully to obtain Trump's tax records, said the Times report makes it even more essential for his committee to get the documents.
"It appears that the President has gamed the tax code to his advantage and used legal fights to delay or avoid paying what he owes," Neal said in a statement on his Facebook page.
"Now, Donald Trump is the boss of the agency he considers an adversary. It is essential that the IRS's presidential audit program remain free of interference."
Biden's campaign team posted a tweet that simply stated how much federal income tax had been paid by teachers ($7,239), firefighters ($5,283) and nurses ($10,216) — all groups that have been hit hard by the pandemic or the West Coast wildfires, two major topics ahead of the debate.
At Tuesday's election debate, millions of Americans will watch as the two antagonists — who depict each other as existential threats to the country — step into the ring live on television after months of shadow-boxing.
Blunders and gaffes
Trump taunted Biden on Sunday with a fresh salvo on his mental acuity.
"I will be strongly demanding a Drug Test of Sleepy Joe Biden prior to, or after, the Debate on Tuesday night," he tweeted, saying he would take one also.