Sen. Bernie Sanders, considered to be one of the frontrunners early in the Democratic presidential primary race, raised $18.2 million in campaign donations in the first quarter Tuesday.

According to campaign manager Faiz Shakir, this $18.2 million was raised with almost 900,000 individual donations, from 525,000 contributors. The average donation was $20, and 99.5% of the donations were $100 or less. Shakir said that a majority of the donors are under 39 years old.

Shakir said that the Sanders has campaign has $28 million in cash on hand.

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Sanders' announcement comes the day after California Sen. Kamala Harris announced that her campaign raised $12 million in the first quarter.

Sanders reported $6 million in fundraising in the first 24 hours of the campaign. The independent senator from Vermont has so far maintained a wide base of support, a holdover from his unsuccessful run in the 2016 Democratic primary. Although he lost that race by 3 million votes, Sanders has had a major influence on progressive politics in recent years.

Several Sanders ideas considered to be on the fringe in 2016, like making Medicare-for-All the law, have since been adopted by some in the mainstream of the Democratic Party, including several presidential candidates. His influence extends beyond the Senate: a Sanders acolyte in the House, Rep. Alexandria Ocasio-Cortez, is one of the rising stars in the party.

Few candidates have announced their first-quarter fundraising totals yet. South Bend Mayor Pete Buttigieg announced $7 million raised Monday morning from over 158,000 donors. His campaign said that 64 percent of the total donations came from contributions of $200 or less.

Harris announced that the $12 million raised in the first quarter came from over 218,000 individual donors, and that 98 percent of the donations were under $100.