Sen. Elizabeth Warren said she has raised $24.6 million for her presidential campaign from July through September, her best quarter to date and a little shy of the $25.3 million that Sen. Bernie Sanders of Vermont took in during the same period.

The haul of the two liberal senators is a reflection of the strength of the Democratic Party’s grass-roots donors. Both have sworn off the practice of wooing wealthy contributors and are focusing on small donors instead; Warren’s campaign reported that its average contribution was $26.

Warren’s haul underscores the advantages for candidates with a loyal base of donors giving in low amounts. Their contributions can fuel campaigns for a longer period, because it takes longer for such donors to reach the $2,800 maximum they can donate to a primary campaign.

Being able to draw on such a base was especially important for Warren (D-Mass.) and Sanders (I-Vt.) in the third quarter — a notoriously difficult time to raise money because of the summer lull, when it’s harder to hold in-person fundraising events with large donors.

“This means our grassroots movement is in an incredible position — to double down on our investments in grassroots organizing, to keep getting Elizabeth’s plans for big, structural change in front of more caucus-goers and voters, and to bring more people into this fight,” according to an email set to be sent to supporters Friday morning from Warren’s campaign manager, Roger Lau.

Warren’s third-quarter figure shows that she has built a small-dollar fundraising machine that is quickly catching up to Sanders’s. Sanders, who is drawing on the donor base he built in the 2016 campaign, still has a formidable fundraising email list that has been without an equal in recent years.

Sanders and Warren came in significantly ahead of their rival Democrats for the quarter. South Bend, Ind., Mayor Pete Buttigeig raised $19.1 million, according to the self-reported figures. And former vice president Joe Biden, who leads many polls, raised about $15.2 million in the quarter, his campaign said.

Warren took in money from 509,000 individual donors over the three-month period, with a total of 943,000 donations — meaning that many of her donors gave more than once. The campaign reported ending the quarter with $25.7 million in cash.

Warren posted $19.1 million in the second quarter and ended that period with $19.7 million in cash, the campaign said.

Candidates have until Oct. 15 to file fundraising reports with the Federal Election Commission, but those with noteworthy numbers typically share their totals soon after a quarter ends. Monday was the final day of the third quarter, which began July 1.

Other Democratic candidates who have released their third-quarter totals so far: Sen. Kamala D. Harris of California ($11.6 million); businessman Andrew Yang ($10 million); Sen. Cory Booker of New Jersey ($6 million); and Sen. Michael F. Bennet of Colorado ($2.1 million).