Vermont Sen. Bernie Sanders greets workers at a rally at the University of California Los Angeles, on March 20, 2019.
Vermont Sen. Bernie Sanders greets workers at a rally at the University of California Los Angeles, on March 20, 2019.

As U.S. Democrats emphasize building their 2020 presidential campaigns on grass-roots support, fewer than half amassed at least 50 percent of their early financial support from small-dollar donations, a Reuters analysis found.

Candidates seeking the White House filed their first-quarter fundraising totals Monday, revealing that many are still relying on checks exceeding $200. Of the 15 Democrats who launched campaigns before April 1, only six of 15 amassed half their hauls from small-dollar donations.

And many candidates are still leaning on donors in their home states for larger checks. Nine Democratic candidates received the bulk of their contributions of $200 or more from their home states, the Reuters analysis found.

Early fundraising prowess can signal the strength of a candidate's campaign. Raising small checks from more donors can act as a test of popular support. Building a broad donor base that stretches beyond a candidate's home state is evidence of gaining traction.

FILE - Democratic presidential candidate and forme
FILE - Democratic presidential candidate and former Texas congressman Beto O'Rourke speaks during his presidential campaign kickoff rally in Houston, March 30, 2019.

Many Democrats have touted their support among so-called "small dollar" donors, those who give less than $200. But only six — U.S. Senator Bernie Sanders, U.S. Senator Elizabeth Warren, former Congressman Beto O'Rourke, Mayor Pete Buttigieg of South Bend, Indiana, U.S. Representative Tulsi Gabbard, and Andrew Yang, a former tech executive — are relying chiefly on those small-dollar donors.

The analysis includes fundraising reports covering the first three months of 2019 by the candidates who launched their campaigns prior to April 1. The field of candidates has since swelled, with 18 Democrats vying to win the party's nomination to challenge President Donald Trump in November 2020.

Sanders, of Vermont, benefited the most from small-dollar donors in the first quarter, with about 84 percent of his $18 million haul coming from individuals who contributed less than $200.

Sanders also had the most geographic diversity in his donations, with California donors accounting for 27 percent of his donations of $200 or more. Less than 2 percent of his donations came from his home state.

South Bend Mayor Pete Buttigieg announces that he
FILE - South Bend Mayor Pete Buttigieg announces that he will seek the Democratic presidential nomination during a rally in South Bend, Ind., April 14, 2019.

Small-dollar donations can help catapult a candidate into the spotlight. Buttigieg until recently did not have a national profile, but raised $7 million during the first quarter of 2019 — of which 64 percent came from small donations.

In a move to show they are serious about eliminating big money from politics, most Democratic presidential candidates have sworn off donations from corporate political fundraising committees. Some have nixed taking checks from registered lobbyists.

The Democratic National Committee announced earlier this year that small-dollar, grass-roots support will be one of the metrics it uses to determine who qualifies to participate in a series of nationally televised primary debates that will begin in June.

Warren — the only candidate to also swear off attending big ticket fundraisers — reported that about 70 percent of the $6 million she raised in the first quarter was from small-dollar donors. Massachusetts donors accounted for 25 percent of contributions over $200.

Democratic Presidential hopeful, Sen. Elizabeth Wa
FILE - Sen. Elizabeth Warren, D-Mass., speaks after she joined striking Stop & Shop supermarket employees on the picket line in Somerville, Mass., April 12, 2019.

O'Rourke reported that 59 percent of his $9.4 million was from donations of $200 or less. More than $2.1 million came from Texans who wrote checks of $200 or more.

On the other end of the spectrum, John Hickenlooper, the former governor of Colorado, raised only 10 percent of his donations in $200 or smaller contributions. There was also little geographic variation among his contributors, with more than 60 percent of donations over $200 coming from his home state.

U.S. Senators Cory Booker of New Jersey and Kirsten Gillibrand of New York each raised about 16 percent of their cash from small-dollar donors.