(CNN) Beto O'Rourke raised $6.1 million in the first 24 hours of his presidential campaign, his campaign said Monday, in what amounts to the largest announced first-day haul of any 2020 Democratic contender to date.

The former Texas congressman raised $6,136,763 in online donations from all 50 states in the first day, his campaign said. That tops the $5.9 million one-day total Sen. Bernie Sanders announced after he launched his campaign. The closest other 2020 Democratic candidate to publicize their first-day fundraising total was California Sen. Kamala Harris at $1.5 million.

The first-day total shows O'Rourke has the potential to recreate the record-smashing fundraising prowess he exhibited during his 2018 US Senate campaign. A more complete picture of what candidates have raised — and how much they spent, particularly on social media advertisements, to raise that money — will come in April, when reports covering the first fundraising quarter are due.

"In just 24 hours, Americans across this country came together to prove that it is possible to run a true grassroots campaign for president -- a campaign by all of us for all of us that answers not to the PACs, corporations, and special interests but to the people," O'Rourke said in a statement announcing the total.

O'Rourke's haul came after he launched his campaign with a video and several campaign stops Thursday in Iowa.

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