WASHINGTON (AFP) - Joe Biden raked in US$6.3 million (S$8.5 million) in the 24 hours since launching his presidential bid, his campaign said on Friday (April 26), outpacing Day 1 fundraising of all other Democrats in the crowded 2020 field.

Online donations to the former vice-president, already considered the frontrunner among the Democrats seeking to challenge President Donald Trump, averaged US$41, and 61 per cent of total money raised came from new donors who were not on earlier Biden e-mail lists.

The dollar figure eclipsed the US$6.1 million opening-day haul by rival Democrat Beto O'Rourke, a former congressman from Texas, and the US$5.9 million raised in 24 hours by liberal Vermont Senator Bernie Sanders, who is second behind Biden in the polls.

"It is crystal clear from the last 24 hours that Americans are ready for dignified leadership, someone who can restore the soul of the nation, rebuild the middle class so everyone gets a fair shot and unite the country behind the core values we all believe in," deputy campaign manager Kate Bedingfield said in a statement.

"That person is Joe Biden, and today's announcement demonstrates Americans agree."

The strong financials come as welcome news to the veteran Democrat currently in his third presidential campaign.

On Thursday, he became the last major candidate to enter the race, and until now has been at a disadvantage in the all-important fund-raising stakes as candidates scramble for resources for what is expected to be a gruelling, year-long primary campaign.