Nick Shalek ’05 said Wednesday that he will not campaign for the Democratic endorsement for a second term as Ward 1 alderman, a move that came as a surprise to some ward leaders and virtually guarantees that the upcoming April endorsement election will be uncontested.

Unless someone files to run by Friday at 5 p.m., Shalek’s decision leaves Rachel Plattus ’09 as the sole contender in an April 11 race specifically designed to broaden the candidate field and increase student participation in the process. But Shalek did not categorically rule out running in the September Democratic primary election or as an independent candidate in the November general election, declining to comment on his future plans.

“My decision is based solely on the need to focus on serving New Haven and the Ward over the next few months,” said Shalek, who also works full time at the Yale Investments Office. “A great deal is happening at the city, particularly with [New Haven] facing the toughest budget in over a decade. Much of my first year on the Board has been about building relationships, learning, and creating momentum around issues that matter to me. I think the most important thing right now is to continue that momentum, be an advocate for worthy causes and good governance, and engage students in city affairs outside of an election process.”

Although a Shalek run in April might have been a formidable challenge to Plattus’ campaign — even though her political apparatus is already well established and staffed — she said Wednesday that she was disappointed that the race will probably be uncontested.

“The advantage of having a campaign with more than one candidate is always that you get to generate a lot of energy about issues that are important to people, so I think in that sense it’s too bad,” Plattus said, adding that she will likely still hold events over the next two months similar to the open discussion on education she held last week. “Nick and I have some differences on some issues, but I respect him … and I wish him well for the rest of the term.”

Several students in Shalek’s inner circle of friends said he had been giving hints for some time that he might not run. Jayson Tischler ’07 said he saw Shalek’s decision as one that turned on his entering into a new “life stage.” Tischler said Shalek had vaguely indicated that he might seek a new job at some point in the near future, but Tischler said he would support Shalek if he chose to run in the primary or general election.

Hugh Baran, co-chair of the Ward 1 Aldermanic Committee, said he was moderately surprised that Shalek decided to forgo the April election, which both he and Shalek had helped to spearhead.

“I’m surprised, but also I’m not because he hadn’t indicated up to this point that he was planning on [running],” Baran said. “But there’s still the possibility for anyone to file.”

But Rebecca Livengood ’07, who won the endorsement of the Democratic Town Committee in 2005 and went on to lose to Shalek in the general election, said she would be satisfied if no one else runs, because she said Plattus is a “great” candidate who presents a “good opportunity for New Haven.”

Some students outside of campus activist circles, however, said they were disappointed. Carmen Lee ’09, a member of the Yale Political Union’s Independent Party, said it was “too bad” that Shalek was not running and called an unopposed Plattus candidacy a “terrible” scenario. She said Plattus’ role in the Roosevelt Institution is not appealing to her.

“Having a predetermined outcome in any race is really, really not fair, especially when that outcome is determined by an activist organization that doesn’t represent most of campus,” Lee said. “Livengood also had that kind of activist apparatus behind her, which I find instinctively off-putting. You have to be realistic [about] what the Board of Aldermen is and not be trying to solve economic disparity in Connecticut and Africa.”

Several students said they were not surprised by Shalek’s decision. Sarah Kellner ’08 said although she would prefer that Plattus face an opponent to encourage campus dialogue on city issues, the fact that Shalek was “publicly humiliated” after being arrested at a bar last summer would make it difficult for him to court voters. Charges against Shalek were dropped soon after the incident.

Ben Eidelson ’08, Plattus’ communications director, said the campaign staff will be meeting privately soon to discuss the most “appropriate” path to take leading up to the April vote. Eidelson said it would be inappropriate for Shalek to run in the primary without seeking the Democratic endorsement.

“We would be extremely surprised given how involved Nick was in formulating the new endorsement process, and the fact that he campaigned last time on the necessity of a new process,” Eidelson said. “We would be pretty shocked if he then circumvented that process to run in a primary in September that he said is not representative because students have just gotten back to campus.”

Though he did not fully explain his intentions for the future, Shalek said he still supported the April endorsement election — but he stopped short of calling it ideal, rather referring to it as simply more fair than the closed-door vote of the Democratic Committee that made endorsements in prior elections.

“I still support the endorsement process and am grateful for the work of my co-chairs and others who helped put it together,” Shalek said. “I believe it is fairer than what it replaced and will be beneficial to the Ward in the future.”

Under the new rules, there are fewer hurdles to filing to run in the Ward 1 endorsement election than in the past. Prospective candidates must collect 80 signatures, fill out the forms available on the Ward 1 Democratic website and submit them by Friday afternoon.

Historically — with the notable exception of Shalek’s successful independent run in 2005 — the winner of the Democratic endorsement has gone on to win the general election. The September primary is generally considered too early in the school year for a non-endorsed Democrat to win, and New Haven Republicans rarely win aldermanic elections. Out of the 30-person Board of Aldermen, only one representative is a Republican.

Representatives and supporters of Plattus’ campaign have called in recent weeks for a “return” to the tradition of a current Yale student serving as Ward 1 Alderman. But non-students have actually served in the job more often than not. In the 23 years since 1983, when Ward 1 became a primarily student-occupied ward, a current student has been in office for only three full calendar years, and only one junior has ever been elected.