Sen. Bernie Sanders was the top fundraiser among 2020 Democrats in the first quarter, bringing in $18.2 million, but he's now been outraised in the second quarter by South Bend Mayor Pete Buttigieg.

Sanders' 2020 campaign raised $18 million in the second quarter, while South Bend Mayor Pete Buttigieg raised $24.8 million.

Facing questions on why Sanders is falling behind Buttigieg in fundraising, the campaign chalked it up to the Vermont senator rejecting the traditional high-dollar fundraising model.

Sanders' campaign manager Faiz Shakir said the Vermont senator isn't raising money at "cushy closed-door high-dollar [fundraisers] in New York City in which people eat Parmesan encrusted salmon on toothpicks."

Sanders' campaign said it raked in nearly one million contributions and their average donation for quarter two was $18, also stating that teachers were the number one profession that donated and the most common employer was Walmart.

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Sen. Bernie Sanders' 2020 campaign was outraised by South Bend Mayor Pete Buttigieg's campaign by nearly $7 million in the second quarter of 2019.

Sander's campaign announced on Tuesday it raised $18 million in this period, while Buttigieg raised $24.8 million.

In the first quarter, Sanders was leading the large pack of candidates vying for the 2020 Democratic nomination in fundraising, but he's now been surpassed by someone who barely anyone had heard of at the beginning of the year.

Sanders' campaign in a press call on Tuesday said in addition to the $18 million from grassroots fundraising it pulled $6 million from other accounts and has roughly $30 million in cash on hand.

Read more: Trump's 2020 campaign raked in a whopping $105 million in the second quarter

Faiz Shakir, the Vermont senator's campaign manager, said 99.3% of the donations were $100 or less and 45% were from donors 39 or younger.

The Sanders' campaign said it raked in nearly one million contributions and their average donation for quarter two was $18, also stating that teachers were the number one profession that donated and the most common employer was Walmart.

Facing questions on Sanders falling behind Buttigieg in fundraising, the campaign chalked it up to the Vermont senator rejecting the traditional high-dollar fundraising model.

Read more: Mayor Pete Buttigieg said Republicans 'have lost all claim to use religious language ever again' because of Trump's immigration policies

Shakir said Sanders isn't raising money at "cushy closed-door high-dollar [fundraisers] in New York City in which people eat Parmesan encrusted salmon on toothpicks."

"This is a movement built by working people all across this country. While other candidates court big money at fancy fundraisers, this campaign is supported by teachers, retail workers, and nurses who are putting what little money they have behind the one candidate who can bring about the transformative change this country needs," Shakir said. "Our strength is in numbers and we have a million person movement committed to this campaign who can give over and over again."