NEW YORK (NYTIMES) - President Donald Trump's campaign is raising money for a prolonged political and legal fight long after Nov 3 and recently began automatically checking a box to withdraw additional weekly contributions from online donors through mid-December - nearly six weeks after Election Day.

Predicting "FRAUD like you've never seen," the language on Mr Trump's website opts contributors into making the weekly postelection donations "to ensure we have the resources to protect the results and keep fighting even after Election Day." Users must proactively click to avoid making multiple contributions.

The unusual postelection revenue stream would help Mr Trump pay off any bills that his campaign accumulates before Tuesday - a campaign spokesperson said no such debts had been incurred - and could help fund a lengthy legal fight if the results are contested.

"This race will be very close, and it is possible that multiple states will require recounts and potential additional spending from our campaign," said Mr Tim Murtaugh, a spokesperson for Mr Trump's campaign. "The election process this year is under extraordinary circumstances, and we are also anticipating that Silicon Valley will attempt to interfere with our online fundraising efforts postelection." Democrats said automatically opting contributors into postelection giving was a misleading tactic.

"They're inventing new deceptive tactics to essentially steal money from people," said a Democratic digital strategist with an expertise in fundraising Mike Nellis. "They're going completely and totally scorched earth on their own supporters. I've never seen anything like this in my life."

Mr Murtaugh said that no one would receive a "recurring charge without their knowledge" and that donors could opt out of recurring contributions both before donating and afterward. "Three days before each recurring charge, donors are emailed a reminder that the charge is about to occur," he said. "There is a one-click link inside this email for donors to cancel if they wish. Our process is extremely transparent."

"When the recount or litigation process ends," Mr Murtaugh added, "the recurring payments will end." The extra donations are just the latest hyperaggressive tactic employed by the Trump operation as it struggles to keep up financially with Mr Joe Biden's campaign.

On Friday, the campaign promised supporters that their contributions would be matched "1000 per cent," after months of ratcheting up the levels of matches that campaign experts said almost surely do not actually exist. (The Trump campaign declined to say if the matches were real; Mr Murtaugh said only that it was a "common fundraising approach" used by both parties.)

"Today in record-breaking achievements of grift," a top digital strategist for Mr Biden Caitlin Mitchell, who wrote mockingly on Twitter of the purported 1,000 per cent match. The Biden campaign said it had never offered donation matches.

The Trump email, which had two flashing-light emoji in the subject line, was one of 21 that blitzed supporters' accounts Friday - nearly one per hour - almost all of which asked for money. For comparison, the Biden campaign sent eight emails Friday.

In the final stretch of the 2020 race, Mr Trump is being dramatically outspent on the airwaves, and as of Oct 14, his campaign treasury had dwindled to US$43.6 million, with US$1.2 million in debts. Mr Biden's campaign reported US$162 million cash on hand that day.

Combined with party funds, Mr Trump had aboutUS$224 million, compared with $335 million for Mr Biden, but party funds cannot be used to pay for many key costs, including campaign personnel and most advertising costs beyond a strict limit.

Since then, Mr Trump's campaign canceled a net total of about US$19 million in reserved television ads, according to data from Advertising Analytics, and the Republican National Committee stepped in to pay for the ads instead, using the limited funds it can spend in coordination with the campaign.

Mr Trump has taken to addressing the financial disadvantage directly at his rallies. "I could have been the greatest political fundraiser," he said Saturday in Pennsylvania, saying he had avoided shaking down wealthy interests for more money.

"We have plenty," he said. "You can only buy so many commercials." It has been a different message to his supporters online, where his campaign has cranked out more frequent and more intense cash solicitations.

The Twitter account @TrumpEmail, which has cataloged all of Mr Trump's email solicitations for nearly three years, provided The New York Times with access to its database, which shows Mr Trump's climbing number of monthly emails this year - from January (63) to May (159) to July (239) to September (330) and roughly 400 in October.

Many messages employ shaming tactics to prod backers into giving. "The President selected YOU to be a part of this exclusive group, so he was really surprised when we told him you STILL hadn't stepped up," read one recent email urging people to donate and activate a "2020 Trump Diamond Card." Gold and platinum cards have also been dangled for donations.

Mr Patrick Ruffini, a Republican pollster who previously worked in digital fundraising, said the Trump campaign's digital marketing tactics mirrored Trump's personality.

"The president doesn't have a filter, and there aren't a lot of restraints on what they'll say or do from a fundraising standpoint either," Mr Ruffini said. He called the campaign an "optimization machine" designed to maximize revenue above all else.