About a fifth of donors have given to more than one Democratic presidential nominee in the first six months of this year, pointing to the difficulty candidates face distinguishing themselves among those giving small amounts at a time.

That revelation comes according to an analysis of ActBlue data, released by the Federal Election Commission this week. ActBlue is an online fundraising platform used by all major Democratic presidential candidates. The data released Thursday offers an in-depth look at how small-dollar, grass-roots donors are shaping the Democratic primary.

Sen. Bernie Sanders (I-Vt.) raised the most money from small donors, collecting $30 million from 746,000 contributors, the highest of any presidential candidate.

Sen. Elizabeth Warren (Mass.) brought in the second-highest haul, raising $17 million from 410,000 individuals. Pete Buttigieg, mayor of South Bend, Ind., came in third, raising $15 million from 376,000 donors.

A handful of donors gave to at least 20 candidates in the first six months of 2019, the ActBlue data shows. Contributions generally ranged from $1 to $20 per candidate, though many donated significantly more to their favorites.

Robert Neill Jr., 61, an investor, farmer and real estate broker, gave between $1 and $5 to 20 Democratic candidates. He also contributed to the campaign of former Massachusetts governor Bill Weld, Trump’s long-shot Republican challenger.

In an interview, he said he wanted to give some of the “second-tier candidates,” like Washington Gov. Jay Inslee and Sen. Cory Booker (N.J.), a shot to show their stuff on the debate stage.

Neill plans to give a larger donation to the Democratic Party’s eventual nominee, but for now, the undecided, longtime Democratic voter from Carrollton, Miss., wants to hear from as many people as possible.

“I like that Tulsi Gabbard is looking at the military industrial complex. She’s voicing some things that no one has brought up since Dwight Eisenhower,” he said about the congresswoman from Hawaii. “There are just a lot of different issues, a lot of issues on the table. Each of the candidates is bringing some of their unique perspectives on that.”

Michael Komblevicz, 44, a sales manager for a telecommunications company in Spokane Valley, Wash., has a very different motivation.

Komblevicz, a Republican, gave widely because he believes a crowded Democratic field will be a “total mess” for the party, as it was for the GOP in 2016. He gave $1 to 20 Democratic candidates to bolster their chances of meeting the party’s fundraising threshold to appear on the Democratic debate stage.

“Honestly, politics is gross,” he said. “It’s like watching a sporting event to me.”

Komblevicz did not vote for President Trump in 2016. He says he is not sure whom he will support in the 2020 general election. He is a fan of former vice president Joe Biden but says Warren is “too socialist.”

Overall, more than 2.3 million people donated $200 or less to the Democratic presidential candidates in the first six months of 2019. These small-dollar contributions totaled nearly $110 million.

Small-dollar donations have played a big role in the primaries so far, thanks to new rules from the Democratic National Committee. Unlike in years past, candidates must gather a certain number of donors to qualify for the debates. As a result, campaigns have competed for a base of supporters who give a few dollars at a time.

Democratic voters interviewed by The Washington Post say they are giving differently than in years past. Rather than simply donating to a favorite candidate, they are offering a few dollars at a time to help certain people raise their profiles or bring their policy ideas to a broader audience.

That competition may help explain why, in recent months, many Democratic candidates who initially distanced themselves from big donors have been holding more traditional fundraisers courting donors who give maximum $2,800 checks at a time.

The only candidate who has completely shunned courting wealthy donors at private fundraisers is Warren. Even so, Warren drew one of the biggest hauls in the second quarter, at $19.1 million — suggesting a potent small-dollar donor base for the candidates who can successfully tap into it.

Earlier this summer, Republicans launched their own small-dollar fundraising platform, named WinRed, in an effort to capi­tal­ize on the president’s small-dollar donor base. They modeled WinRed after ActBlue, though unlike ActBlue, WinRed is a for-profit company.

President Trump has consistently drawn about half or more of his campaign donations from donors giving less than $200, often in the form of buying “Make America Great Again” merchandise or responding to a flurry of email or Facebook advertising appeals by his reelection campaign.