Tuesday's (Sept 29) chaotic presidential debate produced a surge of cash for Mr Joe Biden from Democratic grassroots donors, who poured nearly US$10 million (S$13.6 million) into his campaign between 9pm and midnight.
Mr Biden had his best hour of fund raising in the campaign as the verbal slugfest was winding down, taking in US$3.8 million between 10pm and 11pm, according to a Biden campaign official, 85 per cent of which came via mobile phones.
The campaign received more than 215,000 donations in the three-hour time period, said the official, who asked not to be named because he doesn't speak for the campaign. There were 60,000 first-time donors. The fund raising totals were first reported by a news outlet.
President Donald Trump's campaign has not released figures on its post-debate fund raising.
In August, Mr Biden and the Democratic National Committee erased the financial advantage that Mr Trump's re-election effort held through the campaign, raising a record-breaking US$365 million and ending the month with US$466 million in the bank.
Mr Trump's campaign, the Republican National Committee and two joint fund raising committees that support both entities had US$325 million in the bank.
The cash advantage has allowed Mr Biden to widely outspend Mr Trump in September. The previous VP has spent nearly US$170 million on advertising, including digital, over the month compared to US$68 million for Mr Trump's campaign, according to Advertising Analytics.
Mr Trump has cut advertising in some key battleground states while Mr Biden has expanded spending in key markets.
The campaigns next report detailed information on their fund raising and spending to the Federal Election Commission on Oct 20, exactly two weeks before the Nov 3 election.