Washington — Nearly two dozen Democratic presidential candidates raised more than $3 million total from Michigan donors during the first six months of the year, buoyed in large part by tens of thousands of small-dollar donors.

At least 58,770 Michiganians made about 138,470 contributions to the campaigns of the major Democratic contenders through June 30, according to a campaign finance data analysis by the Center for Public Integrity.

Approximately 10,000 Michigan donors gave to more than one of the 23 Democratic hopefuls, including a St. Joseph woman who opened her wallet to 21 different candidates.

Nearly 1 in 3 of the dollars raised for the Democrats in Michigan went to U.S. Sen. Bernie Sanders, the Vermont independent, who led the pack with $895,500 from roughly 50,900 donors.

Sanders has also raised the most nationally ($46 million) and has the most individual donors among the Democratic candidates.

He was followed by South Bend Mayor Pete Buttigieg with just over $586,000 raised from about 17,050 Michigan donors this year, and Massachusetts U.S. Sen. Elizabeth Warren with nearly $454,700 from 19,500 donors.

Others who raised over $100,000 in Michigan include California U.S. Sen. Kamala Harris ($276,200), former Vice President Joe Biden ($272,150) and former Texas Rep. Beto O’Rourke ($105,400).

The database compiled by the Center for Public Integrity is the most comprehensive look yet at 2020 contributions to the Democrats because it captures the many small-dollar donors giving a total of $200 or less — contributions that are not required to be itemized by the presidential campaigns.

The small-donor donations were reported last week by ActBlue, the online fundraising platform that processes payments for the major Democratic candidates.

The center combined those small-dollar donations with other Federal Election Commission data, making it possible to track an estimated 94 percent of individual donations overall. Not captured by the data set are contributions given outside of ActBlue (such as by mail or in person) where the donor gives less than $200.

"Candidates who aren’t getting those very large donors have been able to compete by having a very large base of donors," said Craig Mauger of the Michigan Campaign Finance Network.

"And people have become smarter in realizing that, although I can't give 1,000 or $1 million to a super PAC, if we pool all these small donors together, that really is something significant. The small donors pooled together can be a pretty powerful force."

The campaigns have also gotten savvier about attracting small-dollar donations, with email blasts and Facebook ads asking for $10, $5, even $1, for instance, Mauger said.

Sanders' operation is particularly adept, building on an already expansive network of online donors that helped him raise money in 2016 when he won Michigan's Democratic primary.

The Center for Public Integrity's analysis found at least 2.4 million people collectively gave roughly $209 million to the campaigns of major Democratic candidates in the first half of 2019, eclipsing the $124 million that President Donald Trump has raised so far toward his 2020 reelection campaign.

Trump has also tapped into small-dollar donors, raising 31 percent of his 2016 campaign haul from donors giving $200 or less, according to his FEC disclosures.

His campaign brought in $56.8 million nationally in the first six months of 2019, including nearly $15 million from small-dollar donors. His campaign said it had 957,000 individual donations, of which 98 percent were $200 or less in the second quarter.

Trump raised at least $478,000 from Michigan donors this year, not including those who gave $200 or less, which have not been disclosed.

Republicans only recently created a fundraising conduit similar to ActBlue called WinRed, and it's too early to potentially use it for analyzing small-dollar contributions.

Individuals may give up to $2,800 per candidate per election for the 2020 cycle. That means the campaigns can return again and again to small-dollar donors before hitting the legal cap.

The Center for Public Integrity determined that roughly 1 in 5 donors gave to two or more Democratic candidates this year — a trend likely related to Democratic National Committee rules requiring candidates to meet certain donor thresholds to qualify for the debate stage, Mauger said.

Among the Michigan donors who gave to two or more contenders, the largest apparent overlap was among roughly 1,500 donors who pumped money to progressives Sanders and Warren.

Nationally, Warren and Sanders had approximately 60,000 donors in common, based on an analysis that identified donors using unique combinations of first name, last name and ZIP code.

Michelle Aaron, a personal injury attorney at the firm Goodman Acker in Southfield, has contributed to six candidates as she's learned more about each. Part of her goal is to engage more in the 2020 election and to signal the strength behind the wide Democratic primary field, she said.

Trump's election in 2016 "made me decide I wanted to get more involved than I ever was before," said Aaron, 38, of Sterling Heights.

"My motivation to give to multiple candidates was to make them eligible for the debates, so their voices could be heard. Also, the more money the Democrats have the better chances they have in the next election."

She donated to Minnesota U.S. Sen. Amy Klobuchar and former housing secretary Julian Castro to help them qualify for the debate stage. She also gave to New York U.S. Sen. Kirsten Gillibrand, Biden and Warren, giving the most to Warren.

"I'm leaning toward Elizabeth Warren," Aaron said. "I like she has so many plans, and that won me over. She seems the most prepared, and she’s really smart, so she’s really impressive when she's speaking about the issues. I don’t necessarily agree with her ideas about healthcare but at least she’s really strong about her position."

Aimin Walsh, 32, a technical writer in St. Joseph, has donated to 21 of the Democratic contenders, in part to compare their online fundraising tactics and tone for her politics blog called "But Their Emails!"

She said she personally favors Buttigieg for his executive and military experience, humility and attitude, calling him the "Mr. Rogers of Politics." She has donated about $250 to him and traveled to South Bend for meetings of supporters called "Pete-ups."

Walsh said she chipped in $1 to most of the other Democratic contenders to get on their email lists so she could compare how they talk to donors vs. non-donors in a format unfiltered by the media or Twitter.

"I've been stunned. Candidates I thought were good when they spoke were horrible in emails. Some resort to fear-mongering. Some put on 'holier-than-thou' airs for why they deserve my money. Some salivate over Trump's attention," Walsh said.

"And some write good, thoughtful emails that educate or entertain me and tell me about the candidate and their vision."

Buttigieg is still her candidate after the experiment, she said, with "no fear tactics, no guilt, no deadlines, no manufactured urgency" in his messages.

"I've surprised myself with how much value I've found in actually reading these political emails, even the ones I can't stand," Walsh said.

"It helps me decide what I want in my next leader, and it helps me see what all the options are out there."

mburke@detroitnews.com