(CNN) Sen. Bernie Sanders has received contributions from 1 million donors, his 2020 campaign announced Thursday.

According to the campaign, it is the first Democratic presidential campaign to cross that threshold this election cycle.

"Our strength is in numbers, and that is why Bernie Sanders is the only candidate who is able to say his campaign will rely only on grassroots funding in both the primary and against Donald Trump," campaign manager Faiz Shakir said. "Like all campaigns we are beholden to our donors, and we're proud to stand with 1 million working people."

Sanders rarely holds fundraisers, and his campaign is primary funded through small, online donations.

Despite the Vermont independent rejecting traditional fundraising routes, like high-dollar fundraisers and personally soliciting funds from donors, he has remained competitive in the money race . Sanders raised $18 million in the second quarter, placing him behind South Bend, Indiana, Mayor Pete Buttigieg ($24.9 million), former Vice President Joe Biden ($22 million) and Sen. Elizabeth Warren of Massachusetts ($19.2 million). But he also finished the second quarter with more cash on hand than any other Democratic campaign, at $27.3 million.

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