Wall Street and finance executives placed their early 2020 bets on a variety of Democratic presidential candidates, from Pete Buttigieg to Kamala Harris, even as the contenders try to distance themselves from big-money donors.

The first-quarter fundraising totals are the latest indication that high-profile Democratic financiers are waiting for the field to thin out before they open their funding networks and checkbooks to potential challengers to President Donald Trump next year.

Some donors have also been eagerly waiting for former Vice President Joe Biden to enter the race before they open their extensive money networks to other candidates, according to people familiar with the deliberations.

Meanwhile, as Democrats vie for limited dollars in a crowded group, Trump's campaign raised a whopping $30 million in the first quarter and has more than $40 million in cash on hand, giving the president a clear edge even as he suffers from low approval ratings.

The early fundraising totals, which were disclosed on Monday in Federal Election Commission filings, show that some players in the financial industry are interested in backing certain candidates early on, including Sens. Cory Booker and Kirsten Gillibrand and former Texas Rep. Beto O'Rourke.

Sen. Bernie Sanders, who led the Democratic fundraising field with an $18 million haul in the first quarter, did not appear to get donations from finance executives. Eighty-four percent of the take came from donations of $200 or less.

Sen. Elizabeth Warren, another longtime critic of Wall Street and big businesses, received few donations from people in the financial industry. Warren raised $6 million, with 70% coming from small donations.

O'Rourke rode a small-donor base to a stunning near-defeat of Republican Sen. Ted Cruz in deep red Texas last year. He has said repeatedly he will not accept any contributions from corporate PACs, lobbyists and special interest groups. However, his stance didn't dissuade some big-money backers to send some checks his way, as he racked up $9.4 million in total donations last quarter.

Mark Gallogly, the co-founder of investment firm Centerbridge Partners, donated $2,800 to O'Rourke's campaign. Gallogly, a major bundler for President Barack Obama in 2008 and 2012, had been telling friends he was leaning toward supporting O'Rourke's candidacy. Bo Crowell, a managing director at investment banking firm Macquarie Capital, also sent $2,800 O'Rourke's way. His LinkedIn page says he's been an investment banker with 17 years of health-care experience.

Harris, Booker, Gillibrand and fellow Sen. Amy Klobuchar have echoed O'Rourke's calls to reject money from PACs and corporations. Yet, also like O'Rourke, they have received support from corporate and finance leaders.

Beverly Anderson, an executive vice president at Wells Fargo, donated $2,800 to Harris' campaign. Tia Breakley, a managing director at private equity behemoth Blackstone, gave Harris $1,000. Blackstone is run by Steve Schwarzman, one of Trump's top supporters. Harris has raked in a total of $12 million since she announced her candidacy in January, putting her among the top tier of Democratic candidates.

Meanwhile, Booker received $2,800 from Mark Robinson, a partner at investment banking titan Centerview Partners, which has advised pharmaceutical and biotech companies. Boaz Weinstein, the founder and chief investment officer of Saba Capital Management, donated $2,800 to Booker.

Saba's Michael D'Angelo, a partner and chief operating officer at the firm, gave Gillibrand $2,800.

Gillibrand finished the quarter bringing in just under $3 million, while Booker saw $5 million added to his campaign coffer.

Read more: Pete Buttigieg raises $1 million within four hours of 2020 campaign announcement

Buttigieg, the South Bend, Indiana, mayor, raised just over $7 million in the first quarter. According to filings, $5,600 came from Stephen Schuler, a director at Chicago-based investment firm Wicklow Capital. During the 2018 congressional midterm elections, Schuler spent well over $1 million in support of Democrats, records show. Employees at Wicklow Capital combined to give at least $11,200 to Buttigieg throughout the most recent quarter. He has publicly sworn off support from corporate PACs and contributions from the fossil fuel industry.

While most of the fundraising for each candidate came through grassroots small donations under $200, political finance veterans say 2020 candidates shouldn't let up in appealing to traditional big-money spenders — particularly if they don't want to play catch-up with Trump during the general election.

"I think this period of a campaign is about building that network, and right now we are relying way too much on digital fundraising," Rufus Gifford, Obama's finance director during his 2012 re-election campaign, told CNBC on Tuesday. "I think we can beat Trump. But can we beat Trump ... being out-raised 3 to 1? Let's be sure that the candidate won't have to spend so much time raising money come the general election."

Representatives for the 2020 campaigns mentioned in this story did not return requests for comment.