Former Vice President Joe Biden’s 2020 presidential campaign raised $6.3 million in its first 24 hours, the campaign announced Friday.

That number is the highest first-day figure of any of the 20 Democrats who have launched campaigns to challenge President Donald Trump for the White House in the 2020 election.

Biden entered the crowded Democratic presidential primary field on Thursday.

An email from 76-year-old political veteran’s campaign said the one-day fundraising total was “proof we are running a truly grassroots campaign.”

Biden’s campaign claimed that 97% of online donations made by nearly 97,000 people came in at less than $200. The average online donation was $41, according to his campaign.

Former Democratic Texas representative and Senate candidate Beto O’Rourke held the previous high, boasting $6.1 million raised in his first day on the trail. Sen. Bernie Sanders, I-Vt., who is running in 2020 as a Democrat, had raised $5.9 million in his first 24 hours.

Biden had faced questions about his ability to raise enough cash in a primary where his many rivals had already been collecting donations and courting donors for months ahead of him.

The six-term Delaware senator, who spent eight years in the White House as President Barack Obama’s veep, received some early criticism from other Democrats in the race for his financial ties.

Biden reportedly attended a fundraiser in Philadelphia on Thursday evening — the first day of his campaign — hosted by Comcast Senior Executive Vice President David Cohen.

Sanders’ campaign had knocked that big-donor event in an email sent that evening under the subject line “Joe Biden”: “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.”

CNBC reported Tuesday that Biden had been reaching out personally to potential backers days before his Thursday campaign announcement.

Biden still has a ways to go to catch up to his competitors in the Democratic “money primary,” some of whom have had months to raise money for their campaigns. Sanders’s White House bid raised $18 million in its first six weeks, according to that campaign.

Of the candidates who posted their hauls in the first fundraising quarter of 2019, however, none came close to Trump’s campaign, which raked in $30 million and boasted more than $40 million cash on hand.

But Biden, who was widely seen as a frontrunner long before he officially joined the race, could get some more help soon from other powerful fundraisers, CNBC has reported. New York Gov. Andrew Cuomo has told associates that he will leverage his vast fundraising network exclusively to Biden, people with direct knowledge of the matter told CNBC.

Former hedge fund executive Eric Mindich, who raised money for Obama’s presidential campaigns, has also told friends he is planning to help with Biden’s fundraising efforts in 2020, CNBC reported.

This story is developing. Please check back for updates.

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