The Bernie Sanders campaign has announced that the contender for the Democratic presidential nomination raised $18 million in this year’s first quarter via about 900,000 donations, putting the independent senator from Vermont ahead of rivals who also have put out their first-quarter fundraising totals.

Candidates have until Monday to disclose their cash hauls for the period, but California Democratic Sen. Kamala Harris, former Texas Rep. Beto O’Rourke, New Jersey Sen. Cory Booker and Pete Buttigieg, the Democratic mayor of South Bend, Ind., joined Sanders in reporting somewhat early.

The Harris campaign said she raised $12 million in the quarter from about 218,000 individual contributions, while O’Rourke’s team said he took in $9 million from 218,000 contributions, with most of that money — $6 million — coming in the first 24 hours after he officially entered the race on March 14. Booker’s campaign said he raised $5 million, and Buttigieg said his total was $7 million from nearly 159,000 donors.

During this week, Minnesota Sen. Amy Klobuchar’s campaign disclosed she had raised $5 million, and Massachusetts Sen. Elizabeth Warren’s team said her total was $6 million.

Entrepreneur Andrew Yang’s campaign also has reported a fundraising haul, saying it has scored $1.7 million from about 80,000 individual donors. Yang has qualified for the Democratic Party’s first presidential primary debates by getting contributions from more than 65,000 donors. Hawaii Democratic Rep. Tulsi Gabbard said she has qualified for the debates by topping that donor threshold as well, but she has not yet disclosed her fundraising haul.

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The Sanders campaign reportedly said it took him longer in 2015 to raise $18 million in the early stages of the 2016 race for the White House — about 21 weeks.

The burn rates that campaigns are showing also reveal an edge for the senator from Vermont, as well as potential trouble for Warren. His disclosures show spending of about $4 million in the first quarter while bringing in $18 million for a burn rate of around 22%. Meanwhile, Warren’s team spent about $5 million while raising $6 million for a burn rate above 80%, though it still had $11 million in cash on hand thanks to rolling over $10 million from her Senate campaign’s account. The data to calculate burn rates wasn’t available for all candidates.

During the 2016 campaign, few candidates had filed fundraising reports by 2015’s first quarter, according to Amy Walter, the Cook Political Report’s national editor.

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But Walter said all contenders had filed by 2015’s second quarter, with the disclosures putting Hillary Clinton at $47.5 million raised in that period, Sanders at $15 million, Jeb Bush at $11 million and Donald Trump at $1.9 million.

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This is an updated version of a report first published on April 2, 2019.