Five takeaways from the Democrats' 2020 fundraising

Here's a look at some of the key takeaways from third-quarter reports Democratic candidates just filed with federal election regulators:

Joe Biden burned through his money

Biden burned through his campaign donations over the summer -- spending more money than he took in and leaving him with just a fraction of the cash available to several of his better-funded rivals for the Democratic presidential nomination.

Biden's campaign entered October with $8.98 million remaining in its bank account, after spending more than $17.6 million during the July-to-September quarter.

Biden raised $15.7 million during the quarter, according to a report filed by his campaign late Tuesday, shortly after the conclusion of the Democratic presidential debate in Westerville, Ohio, sponsored by CNN and The New York Times.

Biden's cash position a little more than three months before the Iowa caucuses puts him at a big financial disadvantage to rivals such as Sanders, who reported having $33.7 million stockpiled for the primary slog ahead.

Two other Democratic presidential candidates -- Warren and South Bend, Indiana, Mayor Pete Buttigieg -- have each stockpiled more than $20 million.

What's Biden spending money on? One-quarter of Biden's spending in the three-month went to payroll, his filings show.

Speaking to reporters Tuesday night following the debate, Biden's aides downplayed the campaign's financial hurdles.

"We've always said that we think this race is going to be a dog fight, that it's going to go long," campaign spokeswoman Kate Bedingfield said. "We are 100% confident that we have what we need to run our race."

Small donations add up for Sanders, Warren

Sanders relied on small-dollar donations for about 60% of his contributions over the summer -- giving him a pool of donors to tap repeatedly before they hit legal contribution limits.

Nearly $15 million -- or about 61% -- of the money Warren raised from individual contributors during the July-to-September fundraising quarter came from donors who donated $200 or less to the senator's presidential campaign. That helped her post one of the biggest fundraising hauls in the crowded field of Democrats vying to face President Donald Trump next year.

By comparison, small donations accounted for less than a third of Biden's donors.

Warren and Sanders, who represent the ultra-progressive wing of their party, swore off big-dollar fundraising in their campaigns for the Democratic presidential nomination, and their financial strength underscores the enthusiasm of online donors in the 2020 election.

They both outraised Biden and Buttigieg -- candidates who have relied, in part, on larger donors to fuel their White House ambitions.

"The concept is now proven: Candidates who want to focus on the people's agenda and be fueled by the people can totally succeed," Adam Green, the co-founder of the Progressive Change Campaign Committee and a Warren supporter, told CNN this week. "That's a sea change."

Warren recently promised to go further and forgo high-dollar fundraisers in the general election should she win the nomination, a stance that drew sharp criticism from Buttigieg.

"We're not going to beat Donald Trump with pocket change," he told Snapchat host Peter Hamby this week.

Staying power for Buttigieg, too

Buttigieg also spent heavily in the July-to-September period -- as he raced to assemble a staff of more than 300 nationally and build a ground game in Iowa ahead of the February 3 caucuses.

He raised a solid $19.1 million during the third quarter -- falling behind only Sanders and Warren. Despite his heavy spending, Buttigieg's strong fundraising over the course of the year has left him flush with cash. He started October with nearly $23.4 million available in his campaign accounts.

His campaign attracted some bold-faced donors in recent months, including designer Isaac Mizrahi and actresses Alyssa Milano and Jennifer Garner.

Self-funding candidates

Steyer plowed a staggering $47.6 million of his hedge-fund fortune into his longshot bid for the White House, filings show. Other contributors donated $2 million, helping him fulfill the minimum donor threshold set by the Democratic National Committee to join Tuesday's debate.

Steyer is not the only self-funder in the race.

Former Maryland Rep. John Delaney continues to put his own money into the race. He donated $400,000 of his own funds to the campaign in the third quarter of this year.

How low can you go?

Among the 12 Democratic candidates who faced off on Tuesday night's debate stage, former Housing and Urban Development Secretary Julian Castro faces the biggest financial peril. The former mayor of San Antonio, Texas, raised nearly $3.5 million, but had just $672,000 remaining in his bank account at the end of September.

Former Reps. Beto O'Rourke of Texas and Tulsi Gabbard of Hawaii had $3.3 million and $2.1 million, respectively, remaining in their bank accounts. Minnesota Sen. Amy Klobuchar, who also joined Tuesday's debate and made forceful attacks on Warren, had nearly $3.7 million left over in her campaign accounts.

Way, way back in the fundraising pack: Wayne Messam, the Miramar, Florida, mayor who has never gained traction in the Democratic presidential nomination.

His campaign reported receipts of exactly $5 in the July-to-September fundraising period in its filing with the Federal Election Commission. And because federal law doesn't require candidates to report details on donors who provide $200 or less to a campaign, it's hard to tell who provided the money. (Messam has had to correct his filings in the past; earlier this year he filed an amended report after mistakenly reporting he had raised nearly twice as much as he had actually collected.)

Tuesday's reports show the Democrat still had a little more than $31,000 remaining in his campaign's bank account.