Vermont Sen. Bernie Sanders' campaign Tuesday announced that it raised $18.2 million from more than 500,000 donors since he got in the 2020 presidential campaign in February.

The haul is the most of any Democratic presidential candidate so far. California Sen. Kamala Harris and South Bend, Ind., Mayor Pete Buttigieg have also reported impressive totals for the first quarter of the year, which ended on Sunday.

Harris has raised $12 million, while Buttigieg, largely unknown before his presidential campaign announcement, has taken in $7 million. The political world is watching to see what ex-Texas Rep. Beto O'Rourke has raised after saying he had pulled in $6.1 million in his first day, topping Sanders' one-day total of $5.9 million.

Sen. Amy Klobuchar of Minnesota and former Colorado Gov. John Hickenlooper each said they raised $1 million in 24 hours. Another candidate to watch is Sen. Elizabeth Warren of Massachusetts, one of the biggest names in the race who raised a relatively modest sum of $300,000 on her first partial day in the race.

The first quarter ended March 31, but campaigns aren't required to report their totals to the Federal Election Commission until April 15.

By the end of 2018, the Trump campaign had raised $67.5 million and spent $55.9 million. (The Trump campaign had raised about $28 million from individual contributions.) Two additional political action committees that function as joint fundraising committees with the Republican National Committee, Trump Victory and Trump Make America Great Again Committee, had raised an additional $100 million.

But the Trump campaign only had about $19 million cash on hand. Part of that is because of how many rallies he's been holding. Before the midterm elections, for example, as NPR's Peter Overby reported, the Trump campaign held 18 rallies in 20 days campaigning for Republican Senate candidates.

The campaign also racked up some $6 million in legal bills with most of it going to "defense attorneys in cases including Trump's alleged affair with porn star Stormy Daniels, Donald Trump Jr.'s meeting with Russians at Trump Tower and several allegations involving Trump's son-in-law, Jared Kushner," Overby reported.

Sanders has $28 million cash on hand, including $14 million the campaign started with. Sanders famously touted during the 2016 race that his average donation was $27. In this bid, it's less — $20. The campaign added that 88 percent of donations were under $200, and a majority of donors were younger than 39 years old.

Sanders' campaign said it has accumulated a total of almost 900,000 contributions in 41 days, a total, it says, took 146 days to reach in his 2016 bid. Of 525,000 individual contributors, roughly 20 percent, or a little over 100,000, are new donors. Sanders has taken the unique step of setting up the ability for donors to make automatic payments to the campaign.

Harris said she had 218,000 contributions; 98 percent were under $100; and the average donation to her campaign was $55. While many Democratic candidates have eschewed raising money in traditional donor circles, Harris has not. She has spent years courting California's donor class, though her campaign says less than 1 percent of her donors cut checks for the maximum $2,800.

Buttigieg, who has seen his name recognition and favorability spike in recent days, said he's had 158,550 donors with an average donation of $36.35 and almost two-thirds of the money raised was from donations of under $200.

"This is a big deal, I've got to tell you," Buttigieg said explaining the numbers in a Facebook video. "This is way ahead of what our original initial goals were. And it's definitely ahead of what people thought we would be able to do, especially when you consider when we launched this exploratory committee, most people had never heard of me."

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