Portland City Council’s two Green Party members are both stepping down later this year, possibly leaving the council without green representatives for the first time in nearly a decade.

City Councilors David Marshall and Kevin Donoghue – both influential and progressive councilors in their mid-30s – will not seek re-election, which also opens the door for two newcomers to represent the two ends of Portland’s urban peninsula. Donoghue represents the East End, while Marshall represents the West End.

Donoghue said in a written statement late Tuesday night that he is “ready for a change” now that his 5-year-old daughter Rosaleen is about to enroll in kindergarten at the East End Community School.

“I am proud to have been elected three times to represent the interests of the district and am gratified that voters provided a mandate for my policy platform focusing on affordable housing and alternative transportation just as many times,” said Donoghue, who represents the East End and works at WEX in South Portland.

Marshall, who among other things helped lead a citizens initiative to support the legalization of marijuana in Portland, has indicated that he will not seek re-election to his West End council seat.

While Portland City Council elections are technically non-partisan – candidates’ party affiliation do not appear on the ballot – the parties play a role in recruiting candidates and forming alliances. Democrats hold all of the other seats on the council.

The council is losing two of its most vocal supporters of affordable housing and public transportation at a time when the city is trying to boost supply of much needed rental housing and as city planners are changing the city’s streets to be less focused on cars and more focused on alternative modes of transportation. Significant proposals championed by the duo, including a proposal to convert High and State streets to two-ways roads and an ordinance to require some developers to include middle-class housing in large development projects, have yet to be decided by the council.

“Portland is an expensive place to live and it needs to be equally aggressive about housing development and investing in public education if it wants to retain working families,” Donoghue said.

Both Donoghue and Marshall were elected in 2006 and are completing their third, three-year terms in the traditional Democratic stronghold. Their election ushered in a series of electoral wins for the Green Party in Portland, which has members serving on the council, school board and state legislature. It also marked the first time that people in their 20s were elected to the council.

The Green Party’s success has been a sore spot for area Democrats, who in 2007 spent $3,000 on as many as 200 campaign signs warning voters, “These Greens Cause Chaos,” a nod to the failed effort to redevelop the Maine State Pier, the arrests of two Green school board members and a $2 million school budget deficit.

There are currently three Green Party members serving on the school board.

Donoghue and Marshall met a few years before their first election when they were both living in the West End and quickly bonded over discussions about urban planning, Marshall said. Donoghue was a student at the Muskie School for Public Service and chairman of the Green Independent Party, who was recruiting candidates at the time, he said.

In 2006, the two decided to run for council at the same and even produced a joint campaign photo of the two standing in the middle of High Street, which divides the districts. In the photo, Marshall holds up three fingers signifying a “W” for west side and Donoghue hold three fingers across his chest signifying an “E” for east side.

Upon winning, they were natural allies on a council that seemed to be in lock-step before an issue was ever discussed in council chambers, Marshall said. During their first meeting, they felt push back against a ban on formula franchises such as Hooters that was enacted prior to their inauguration and later repealed and then became embroiled in the battle to redevelopment the Maine State Pier.

“It was kind of trial by fire,” Marshall said. “It’s always good to have ally when you’re going into City Hall with everything that we were up against.”

While sharing similar views, Marshall and Donoghue have distinct political styles.

Marshall has been eager to be the public face of citywide issues, speaking out in favor of marijuana legalization and against tar sands oil, plastic bags and plastic foam containers. He is quick to return calls and will often speak at length about a range of topics.

Donoghue, meanwhile, prefers to work more behind the scenes and hasn’t publicly campaigned for Green Party issues. He prefers to communicate by email and is intensely interested in the subtle nuances of housing, zoning and transportation policies.

Marshall said he and Donoghue had discussed their plans for this November but reached their decisions independently.

“I can’t say that we made a pact to leave the council at the same time or anything, but I can say there is something poetic about it,” he said.

Marshall, a painter who first got his start in politics after discovering that the city required artists to get permits to paint in public, came in fourth in a 15-way race for mayor in 2011. He said it was a difficult decision not to seek re-election after serving for nine years. However, the 37-year-old is looking forward to spending more time with his wife and focusing on his painting and rental properties.

Donoghue, 36, could not be reached for comment on Wednesday. But he made headlines before he was elected to the council in 2006 by advocating for the city to adopt an inclusionary zoning ordinance, which would require developments of a certain size to include housing that was affordable to middle class workers. The council is currently considering an inclusionary zoning ordinance. He won his seat in the council later that year, campaigning on a platform of increasing affordable housing, limiting the conversions of apartments into condominiums and increasing bike lanes, among other issues.

Marshall said he expects the Greens to continue to be a political force. “I think there will be other Greens who will serve on the council,” he said.

Coincidentally, the chairman of the city’s Green Independent Committee announced he is running for mayor.

Portland Green-Independent Committee Secretary Mako Bates, who authored a proposed ordinance that would establish a minimum wage of $15 an hour, is seeking Marshall’s District 2 seat. Spencer Thibodeau, a 27-year-old Democrat and real estate attorney at the Portland-based law firm Verrill Dana, has also taken out nomination papers for that seat.

In Donoghue’s District 1, Brandon Mazer, a 29-year-old Democrat and attorney who is the general counsel for Shipyard Brewing Co., has taken out nomination papers. Independent Steven A.M. Jefairjian, a 63-year-old retired baker who lives on North Street, has also taken out nomination papers for that seat.

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