WASHINGTON (Reuters) - U.S. Democratic presidential candidate Joe Biden raised $6.3 million in the first 24 hours of his campaign, providing a stronger showing than any of his rivals.

Biden, 76, brought in the bulk of that haul through smaller contributions, his campaign spokesman TJ Ducklo wrote on Twitter, with 97 percent of those donations under $200.

He bested the rest of the Democratic field in first-day fundraising, including Bernie Sanders, who raised $5.9 million, and Beto O’Rourke, who brought in $6.1 million.

Prior to entering the race on Thursday, Biden faced speculation that he was going to be unable to raise small-dollar donations via the Internet - which has been viewed as a test of viability and support in the Democratic Party.

To qualify for the first debate in June, candidates need to receive donations from 65,000 different donors. Biden reached that mark in the first 12 hours of his campaign, Ducklo said.

Biden has joined most of the rest of the Democratic field in swearing off donations from Washington lobbyists and PACs associated with corporations. But he did hold a fundraiser on the first day of his campaign at the Philadelphia home of David Cohen, a Comcast executive.

Biden served as former President Barack Obama’s vice president for two terms. He is competing with 19 others for the Democratic presidential nomination and the chance to likely face President Donald Trump next year in the general election.