Rep. Chris Van Hollen (D-Md.) raised $950,000 in the third quarter, his lowest reported fundraising numbers since entering the race to succeed Sen. Barbara Mikulski (D-Md.). (Andrew Harnik/For The Washington Post)

Rep. Donna F. Edwards raised more money this summer than she did in the second quarter of the calendar year, but still trails Rep. Chris Van Hollen (D-Md.) by a huge financial margin in her primary bid to fill the seat of retiring Sen. Barbara Mikulski.

Edwards, who leads Van Hollen by ten points in a new Washington Post-University of Maryland poll, raised $638,524 in the three months ending September 30, more than the $590,000 she collected in the second quarter, according to new filings with the Federal Election Commission.

Van Hollen raised $950,000 in the third quarter of 2015, a slower fundraising pace than he reported earlier in the year. But he has $4.1 million cash on hand, compared to Edwards’ $368,500.

The Van Hollen campaign said Thursday that more than three-fourths of its donations came from Maryland residents and the number of grassroots donors have “increased nearly sevenfold since the first fundraising quarter.”

A third Democratic member of Congress from Maryland, Rep. Elijah Cummings, is weighing whether to enter the Senate race. The Post-U.Md poll shows that he would lead Edwards and Van Hollen by 13 points if he became a candidate.

Rep. Chris Van Hollen (right) had a 3-to-1 fundraising advantage over Rep. Donna Edwards, (left) D-Md., going into the third quarter. Edwards has not yet released her numbers.

Bill Turque contributed to this report, which has been updated.