A campaign rival says Brown didn’t gather enough legitimate signatures to make the ballot. (Bill O'Leary/The Washington Post)

A D.C. Council candidate says incumbent Michael A. Brown (I-At Large) should be ruled ineligible to appear on the Nov. 6 ballot after his campaign scrutinized Brown’s nominating petitions.

David Grosso, an independent running against Brown, on Monday challenged about 2,100 of the nearly 4,700 signatures Brown submitted to the D.C. Board of Elections. If upheld by the board, that would leave Brown well short of the 3,000 signatures necessary to appear on the ballot.

Asher Corson, a spokesman for the Brown campaign, said he had not seen the specific challenges but said the campaign was not especially concerned.

“It’s not up to our opponents whether we qualify for the ballot; that is up to the Board of Elections,” he said. “We’re confident in our signatures and petitions, and Michael Brown will be on the ballot.”

Grosso said he and his campaign volunteers identified a number of concerns, including signatures from unregistered voters, signers listing addresses different from those in voter records, duplicate signatures, undated signatures and ineligible circulators.

“We’re just basically doing basic due diligence,” he said, adding that he’s confident that the challenges will be sustained and Brown will be booted from the ballot.

While it’s not uncommon for candidates to have their ballot petitions challenged, it’s somewhat rare for a candidate to personally challenge his or her competition. Most often, campaigns will have a surrogate engage in the nitty-gritty politicking of filing a challenge with elections officials.

Grosso said he wanted to “stand up in front of the campaign” rather than find a surrogate. “Our whole message has been about transparency,” he said. “I felt the responsibility to stand up and do it myself. It’s part of the campaign process.”

In the coming days, elections staff will review Grosso’s claims and report to board members on how many challenges can be confirmed. The board must make a final ruling on the challenges by Sept. 10.

UPDATE, 8/21, 11:10 A.M.: Activist Dorothy Brizill is also challenging Brown’s petitions, according to the board. Note that Brizill was among a group who successfully challenged former mayor Anthony A. Williams’s ballot petitions in 2002.

Dorothy Brizill has filed a challenge to Petitions of Michael Brown, candidate for At-Large Member of the Council. #DCision12

— DCBOEE (@DCBOEE) August 21, 2012