Carrie Levine for CPI/538:

But the time and energy going into cultivating a grassroots donor base early in the election cycle also carries clear benefits for the party and its eventual nominee — namely, a potentially massive pool of proven donors who could be tapped again in the general election.

Presidential candidates have, of course, achieved varying degrees of success in their attempts to court small dollars. Topping the list: Sanders, who raised 84 percent of his new money from donors giving $200 or less. Compare that to former Colorado Gov. John Hickenlooper, who raised 10 percent of his cash from small donors.

More than half the money that 14 Democratic candidates for president raised from individual donors during the first quarter of 2019 came from donors giving a total of $200 or less. That compares to less than a third among a smaller Democratic field of primary candidates in early 2015.

The Democratic National Committee’s decision to use grassroots fundraising as one of two ways to earn a spot in the first two primary debates — candidates must demonstrate their campaigns have received contributions from at least 65,000 unique donors and a minimum of 200 unique donors per state in at least 20 states — was “a new wrinkle which elevates small dollars,” said David Karpf, a professor at George Washington University who studies politics and digital strategy.