NORTHAMPTON — A third candidate entered the race Friday for the at-large City Council seat vacated by Jesse Adams.

Mary “Mimi” Odgers, 46, of 97 Glendale Road, who works as an administrative assistant at Amherst College, took out nomination papers and said she  is working to collect signatures.

Candidates have until 5 p.m. Wednesday to gather 100 signatures and submit them to the registrar of voters for validation. Once that is complete, paperwork must  be submitted to City Clerk Wendy Mazza by 5 p.m. on May 23 to get on the ballot.

The other declared candidates are Ryan O’Donnell, of 36 Day Ave., who represents Ward 3 on the council and is its vice president, and Andrew Smith, of 10 Myrtle St.

If all three candidates accomplish those steps, a preliminary election would be held July 7 to whittle the field to the top two vote-getters who would continue on to the  final election  Aug. 4.

“It’ll be a lot of work in a short period of time,” said Odgers about meeting the Wednesday deadline. “However, I’m not concerned. I think I can gather the signatures.”

Odgers was an outspoken opponent of the landfill expansion about six years ago, served on the city’s solid waste task force, and later was campaign manager for Michael Bardsley’s second mayoral run in 2011. Mayor David Narkewicz defeated Bardsley in that race.

“I’ve wanted to have an opportunity to be more involved,” said Odgers. “And so when this situation presented itself, it seemed like the right opportunity to jump in and see what I could do.”

Odgers said she’s concerned about Northampton’s economy, and she hopes to bring diversity to the council.

“I have concerns about downtown businesses,” she said. “There’s no diversity on the council — I would like there to be some more outreach.”

Smith is the conservation and sustainability director for the City of Holyoke. O’Donnell is a consultant for nonprofit agencies.

Amanda Drane can be contacted at adrane@gazettenet.com.