WASHINGTON (CNN) Bernie Sanders, a one-time political insurgent, has cemented his role as the fundraising frontrunner of the 2020 Democratic field -- as many of his rivals report pulling in just a fraction of the $18.2 million the Vermont senator collected during the first 41 days of his presidential campaign.

Despite Sanders' early role as the party's fundraising leader, no candidate is setting fundraising records as a crowded field of nearly 20 Democrats jockeys for attention from voters and donors.

In the 2008 campaign, when Democrats and Republicans fielded multiple candidates in the wide-open race to succeed George W. Bush, two Democrats -- Hillary Clinton and Barack Obama -- led the way, raising more than $25 million apiece in the first quarter.

In the 2020 race for the Democratic nomination, no one comes close to the fundraising prowess of either Clinton or Obama.

Candidates who began their presidential campaigns before the end of March have to disclose the details of their fundraising and spending to the Federal Election Commission by the end of the day Monday.

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