Sen. Bernie Sanders, I-Vt., announced Wednesday morning his campaign has hauled in $6 million one day after his presidential announcement.

Sanders, whose 2016 presidential campaign mantra centered around grassroots campaign donations and a rejection of corporate and PAC money, announced in a tweet he received donations from 225,000 contributors and kept an average of $27 per donation. The campaign announced mid-day Tuesday that Sanders had received $3.3 million in online contributions 12 hours after the announcement ran on Vermont Public Radio.

The $27 average campaign contribution has become emblematic of the Sanders campaign since the 2016 race. Multiple supporters responded to Sanders' online fundraising posts, taking screenshots of their $27 monthly recurring donations. Some supporters urged donors on the campaign's social media platforms to give separate donations of $27 rather than one donation of a larger amount.

The haul sends a clear message to the rest of the crowded Democratic field. California Sen. Kamala Harris, who stated last year that she would not be receiving any more corporate PAC money, raised $1.5 million in the 24 hours after her campaign announcement. Both Sanders and Harris have out-raised the rest of the Democratic field, including Sens. Amy Klobuchar of Minnesota and Elizabeth Warren of Massachusetts.

"I'm running for president because a great nation is judged not by how many billionaires and nuclear weapons it has by how it treats the most vulnerable," the campaign stated after the fundraising announcement Wednesday. "The elderly, the children, our veterans, the sick and the poor."

Sanders maintained a robust national campaign infrastructure after his 2016 Democratic primary loss to Hillary Clinton and is seen as one of the clear top-tier candidates for 2020, according to polling. A Hill-HarrisX poll released Tuesday showed Joe Biden remains on top of Sanders by 2 percentage points. The former vice president has yet to announce a decision on a presidential run.

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