Sen. Bernie Sanders raised just under $6 million from about 223,000 people in the 24 hours after he announced his bid for president — making the Vermont senator the clear frontrunner in grassroots fundraising.

Contributors also pledged about $600,000 in donations that will recur each month, the Sanders team announced.

The candidate had surpassed the $4 million mark on Tuesday evening, about 12 hours after he announced his campaign.

Sanders made his average campaign donation of approximately $27 a campaign slogan when he ran against former secretary of state Hillary Clinton in 2016. 

Small dollar donations will be a key metric of a candidate’s strength, especially given that many candidates have promised to eschew money from corporate PACs.

Sanders outpaced two of his colleagues in the Senate.

Sen. Kamala Harris of California reported raising $1.5 million in the 24 hours after her January rollout. Sanders raised that sum in four hours.

Sen. Amy Klobuchar hit the $1 million mark 48 hours after her Minnesota announcement earlier this month.

It’s unclear how the fundraising numbers of other senators in the race  stack up.

Sens. Elizabeth Warren of Massachusetts, Cory Booker of New Jersey and Kirsten Gillibrand of New York have provided few details about their early contributions.

A early glimpse of contributions to Warren, among the first candidates to announce a bid, was made available though a year-end FEC report filed by ActBlue, a clearinghouse for Democratic donations.

Warren raised more than $299,000 through the site on the day she launched an exploratory committee, with an average donation of $37, Politico reported.

But more information won’t be available until their committees file their first quarterly reports, which are due by April 15.

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