Omar Woodard, a nonprofit leader and former campaign strategist, said Friday that he’s ending his short-lived campaign for City Council due to a lack of legitimate signatures on his nominating paperwork.

Woodard, 35, was seen as a credible challenger to Council President Darrell L. Clarke, who hasn’t faced opposition for his North Philadelphia seat in a primary since 2011. Sheila Armstrong, a former legislative assistant and advocate for the homeless, remains in the race.

Woodard said Friday that his campaign reviewed the 1,014 signatures in anticipation of a challenge, and realized too many were likely to be disqualified. Candidates for district Council seats need 750 signatures from registered members of their party living in that district. Candidates for district Council typically file at least three times the required number of signatures to fend off any challenges. As of Friday afternoon, Woodard hadn’t officially submitted paperwork to withdraw from the race.

Armstrong submitted 1,025 signatures to the Board of Elections.

“We didn’t get to the number we needed, and while it’s disappointing, it is the process, and we came up short,” Woodard said. “We realized some people — it wasn’t just that they weren’t registered in the district, they weren’t registered at all,” he said.

Woodard, who was gearing up to run on an anti-poverty platform, said that speaks to a larger issue of poverty in the 5th District, covering much of North Philadelphia, and to the need to get more potential voters registered. “I think it’s a fundamental issue, which I’ll focus on,” he said.

Woodard’s late entry into the race — he announced three weeks ago — could have had an impact on his ability to get signatures and raise money. It’s unclear if he’d have had the resources to run a competitive race against Clarke, though there was excitement surrounding his candidacy. Woodard worked for Anthony H. Williams’ mayoral campaign in 2015 and on occasion stood in for Williams at debates and forums.

He said he will return to his position as executive director of the nonprofit Greenlight Fund, and doesn’t anticipate running for office again any time soon. The organization, which works with youth and families in high-poverty areas, had suggested on its website that Woodard’s run might be short-lived.

On his profile page on the website he is described as “currently on a leave of absence with expected return at the end of May 2019.”

“Over the last three weeks I’ve learned so much about North Philadelphia and both the challenges and the opportunities in the district and across the city.... I hope the rest of the candidates recognize the immense opportunity to learn about your neighborhood and the people who live in it, and to focus on what’s in the best interest of people.”

The May 21 primary has one of the most crowded slate of candidates running for Council since the late 1980s. Clarke is one of eight incumbent district Council members facing a challenger.

Staff writer Chris Brennan contributed to this article.