Prominent leaders within the movement included poet and publisher Martin Butler, as well as educator Henry Harvey Stuart, who formed a Fredericton local of the new Socialist Party of Canada in 1905.

A strong believer in building alliances among the province's social movements, Stuart was later an influential figure in the Co-operative Commonwealth Federation to the time of his death in 1952.

A. Mugridge, a trade unionist and the chief electrician at the Saint John Drydock and Shipbuilding Company, the CCF won 11.7 percent of the vote in New Brunswick's 1944 provincial election.

Prospects were not good during the 1960s, however, as the province's new Liberal premier, Louis J. Robichaud, was a left-of-centre populist politician who won three successive provincial elections and introduced significant social reforms.

[4] During the late 1970s, under the leadership of John LaBossiere, the party increasingly adopted policy positions that reflected feminist and environmentalist concerns, including opposition to aerial spruce budworm spraying and the construction of the Point Lepreau nuclear plant.

Along with promoting traditional social-democratic NDP policies, the party also attacked government patronage and poor fiscal management.

After the one-sided 1987 election, Premier McKenna allowed leaders of the unrepresented parties to ask questions in the legislature and in the public accounts committee.

Her media presence and political stature increased significantly, and she was sometimes referred to by cabinet ministers as the unofficial Leader of the Opposition.

During her time in the legislature, Weir proved a strong critic of McKenna's neo-liberal policies, successfully attacking public-private partnerships such as a plan to have a youth detention centre built and operated by an American corporation.

[9] Despite Weir's personal popularity and her ability to attract strong candidates, she was not able to add extra seats to the party caucus.

Allison Brewer was elected as party leader in September 2005, but faced challenges due to her inability to speak French and her lack of experience in electoral politics.

The party more than doubled its share of the vote, returning to the levels achieved under Little and Weir, but no candidate, including Duguay, won a seat.

[10] He then continued the process of changing the party's policies and organization, in line with the Third Way model associated with former British prime minister Tony Blair, whom Cardy admired.

[11] By 2014, however, Cardy's political strategy was attracting criticism, especially on issues of policies on resource development in forestry, oil pipelines and shale gas.

[12] These factors contributed to the defection of some NDP supporters, including former leader Allison Brewer, to the Green Party of New Brunswick, who were successful in electing David Coon in Fredericton South.

Cardy announced plans to resign at the next party convention, but this was suspended to enable him to run in an unexpected byelection in Saint John East in November 2014, though without success.

Criticism of Cardy's policies and leadership style increased, with concerns expressed by veteran leaders such as federal NDP MP Yvon Godin and Daniel Légère, president of the Canadian Union of Public Employees, New Brunswick.

[15] On 10 August 2017, Jennifer McKenzie of St. Martins, a rural community east of Saint John, was confirmed as the new leader of the party.

An electrical engineer and tech entrepreneur by background, McKenzie ran for the NDP leadership on a pledge to bring the party back to its traditions of advancing social, environmental and economic justice.

[17] "I am a socialist and I believe in the power of people working together," McKenzie stated at a press conference, "I hope to take this party into the future based on the solid principles on which the New Democrats are founded.

[26] Prospects for renewal continued to be discouraging when it was announced, in a joint statement on 3 September, that fourteen candidates who ran for the NDP in the 2018 provincial election were joining the Greens.

[29] A news story later revealed that one of the candidates who led the move to leave the NDP had failed to qualify for the party leadership contest.

[31] In April 2020, however, party president Cyprien Okana announced a decision to postpone the convention due to the emergency conditions created by the COVID-19 pandemic.

[34] Thomason resigned as interim leader on 15 November 2020, and was quickly succeeded by party communications director Nathan Davis, who stepped down almost immediately, citing a change in circumstances following a family emergency.

[37] [check quotation syntax] In May 2022, ahead of two by-elections in which the NDP failed to nominate candidates, the CBC reported that Thomason had lost a non-binding confidence vote by the party's executive council.