Former Vice President Joe Biden’s 2020 campaign is off to a strong start, announcing on Friday that it raised $6.3 million in its first 24 hours.

First day fundraising is often a telling sign of popularity with Biden raising the most on his first day out of all of his 2020 Democratic opponents, including beating out big online fundraisers, Sen. Bernie Sanders (I-Vt.), who raised $5.9 billion, and Beto O’Rourke, who raised $6.1 billion.

Biden started out his long-anticipated campaign run for president as a front runner, the best known politician in the race, but many were concerned about how the former vice president would do financially with most campaigns now funded by small dollar donors.

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Although Biden’s campaign has said 97 percent of online donations were under $200, which accounted for more than half of his donors, Sanders and Rourke both had significantly more donors on their first day of fundraising, with Sanders having more than 200,000 contributors to Biden’s 96,000.

Leading up to Friday, Biden stressed the importance of the first day of fundraising. He also attended a private fundraiser Friday evening at the home of Comcast executive David Cohen, which did not go unnoticed by his opponents.

“How did Joe Biden raise so much money in one day? Well, it helps that he hosted a swanky private fundraiser for wealthy donors at the home of the guy who runs Comcast’s lobbying shop,” said Sen. Elizabeth Warren’s campaign team in a fundraising email.

Sanders team responded in a similar fundraising email. “It’s a big day in the Democratic primary and we’re hoping to end it strong. Not with a fundraiser in the home of a corporate lobbyist, but with an overwhelming number of individual donations in response to today’s news,” it wrote.