According to The New York Times report published on Saturday, Trump's supporters ended up making more donations than they intended as the campaign used pre-ticked boxes on fundraising emails, tricking them to make repeat donations while they intended to make just one-off payment.

As people started complaining that more money was deducted from their accounts than they had made payments for, Trump's re-election campaign was forced to issue $122.7 million in refunds to supporters in 2020, amounting to nearly 11 per cent of the money it raised, said the report.

The Trump campaign and the company that processed its online donations, WinRed, had begun using dark patterns by June 2020.

This refers to computer interfaces that the campaign designed to trick people to make repeated monthly and weekly donations by pre-checking the checkboxes for such options, thereby burying the fine print under paragraphs of bold text.

Thus unless donors inspected the fine print of an online disclaimer and manually untick the pre-checked boxes, they were forced to pay far more than they intended until Election Day arrived.

One Kansas City supporter account got tapped for $3,000 one month when the person intended to make donation of $500.

For another supporter, a $990 donation had become $8,000.

Playing down the claims of widespread fraud, Trump spokesperson Jason Miller told The New York Times that internal data determined 0.87 per cent of its WinRed transactions were subject to "formal" credit card disputes.

"The fact we had a dispute rate of less than 1 per cent of total donations despite raising more grass-roots money than any campaign in history is remarkable," Miller was quoted as saying.