The election of Zohran Kwame Mamdani as mayor of New York City was an unexpected event. In a political environment dominated by major financial interests and powerful lobbies, it seemed inconceivable that a little-known 34-year-old Muslim socialist with little money to fund a campaign would win the mayoralty of the largest city in the United States.

In the capital of capitalism, billionaires opposed him, as did the President of the United States, the New York Times, and even the Democratic Party itself, which favoured his more experienced, better-known, and far better-funded opponent. Yet, Mamdani did it, delivering a rare and brilliant victory for the Left that resonates far beyond the US.

Building on this victory, we offer some observations, hoping to spark discussion, enrich understanding, and ultimately inspire the Left in Greece, Europe, and elsewhere.

Two principles guided Mamdani’s path, and he never deviated from either: the supreme importance of economic justice and the need to end the genocide in Palestine.

His principled stance lent a dignity to his campaign that allowed him to transcend the criticism of and the propaganda funded by billionaires such as Michael Bloomberg and Bill Ackman; it also allowed him to win the support of about one third of Jewish voters. This clear stance provides a model of principled internationalism.

Mamdani built upon a US socialist movement that Bernie Sanders has been leading since the US Presidential election of 2016.

The socialist senator from Vermont has mobilised a broad and diverse base of support with a clear message about the injustice of economic exploitation by the rich, an increase in the minimum wage, and the creation of a national healthcare system for everyone. Mamdani’s message of making New York City affordable by freezing rent increases for rent-stabilised apartments, providing universal childcare, opening municipally operated grocery stores, and making buses free represents a municipal version of the Sanders platform for a city in which one in four residents lives in poverty and reflects the core, transformative agenda of the DiEM25 movement – tackling the crisis of affordability through concrete policies.

Mamdani built his political platform by focusing on universal material concerns like the high cost of living. In places such as Astoria, Queens and other working- and middle-class sections of New York City, Mamdani heard about the high cost of living, and he sought to build support across working-class communities, who would embrace his affordability agenda.

Mamdani defied the typical narrative of the Left, which is often against the status quo, by offering a positive message about affordability, from which he never strayed.

Witness the recent press conference in the Oval Office at which Mamdani was asked repeatedly about his ideological differences with Donald Trump. Making New York City affordable was really his only answer.

Mamdani successfully faced a slate of corrupt and disgraced opponents.

Mamdani successfully faced a corrupt and disgraced establishment opponent. In the Democratic primary, he defeated former Governor Andrew Cuomo, who had previously resigned as Governor of New York after several women accused him of sexual harassment. The incumbent mayor, Eric Adams, had withdrawn from the race before the election.

Mamdani owes his electoral victory to an extraordinary campaign organisation. In a city of 8 million people, the campaign comprised over 100,000 volunteers, who made millions of calls to prospective voters, and who knocked on millions of doors. The energy and enthusiasm behind these numbers is difficult to quantify. The effort resulted in 1,036,051 votes and a win with 50.5% of the vote in the general election on November 4, 2025.

Although Mamdani’s victory represents a rare example of leftist electoral success, the path ahead remains uncertain – as shown by SYRIZA in 2015. The financial interests that opposed him before the election will not stop, and the complex social and political balances of New York City further highlight the challenges he faces. Notable immediate challenges include:

Mamdani lacks the democratic institutions that are necessary for building political consensus and from which to draw support when he is tested. This observation represents a weakness of the Left in the United States.

Mamdani lacks the strong, democratic institutions – a rooted political party, deep ties to organised labour – that are necessary for building political consensus and from which to draw support when he is tested. This highlights a critical structural weakness of the US left, one that DiEM25 was founded to overcome in Europe by building a transnational democratic pillar.

Mamdani plans to maintain Jessica Tisch as commissioner of the New York Police Department, essentially the head of the city’s repressive apparatus.

A key governance challenge will be confronting the city’s repressive apparatus. The Tisch family, to which current NYPD Commissioner Jessica Tisch belongs, is among the richest and most powerful families in New York, supporters of the Republican party and of Israel. Norman Finkelstein, the notable academic and critic of the Israeli genocide of Palestinians, recently asked whether the NYPD would ever act against a figure like Benjamin Netanyahu, as Mamdani has said he would if the Israeli prime minister set foot in the city. This question underscores the immense difficulty of translating radical principles into state power.

Assessment of the Mamdani campaign

Mamdani’s victory demonstrates that political change requires a clear vision, practical measures, and active citizen participation. His campaign mobilised thousands of volunteers, who made millions of phone calls and home visits, transforming support into effective action.

Mamdani’s success combines social justice, affordable living, and organisational strength, offering valuable lessons for any effort to effect change in cities and societies.

For DiEM25, this victory validates our core principles and offers a powerful lesson: winning is possible when we anchor our politics in material needs, moral clarity, and unmatched grassroots mobilisation. Let this inspire our pan-European struggle.

To learn more, join the movement at DiEM25.org and follow @MERA25USA

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