In Tuesday’s mayoral election, Zohran Mamdani captured more than one million votes across New York’s diverse electorate. Most notably, the democratic socialist made huge inroads with black and Hispanic voters in the Bronx and Queens.

These two groups backed Andrew Cuomo heavily in the Democratic primary but swung to Mamdani in the general election. Once wary of him — particularly older voters and union households who doubted his promises on housing and transit — they ultimately decided to give him a chance.

Mamdani achieved this by winning them over to his affordability agenda, mobilising an army of union-aligned canvassers across outer-borough neighbourhoods, and delivering his message in multiple languages. Early in the campaign, he took the unusual step for a non-Latino candidate of releasing a full Spanish-language ad — speaking less than fluently, but with the conviction of someone who cared enough to try. This culturally fluent approach paid dividends. He won clear majorities of both Latino and black voters, especially in the working-class enclaves of the Bronx and Queens.

Mamdani’s message resonated in these two boroughs, where the cost-of-living crisis is felt most acutely. As of this year, more than half of New York City renters were considered rent-burdened, and over one million households paid more than 30% of their income on rent. In the Bronx — the poorest borough, with a majority black and Latino population — nearly 48% of renters were rent-burdened.

The mayor-elect, son of immigrants, came across as a candidate who understood ordinary New Yorkers’ struggles, which Cuomo failed to do. While Mamdani is neither black (unless for a college application) nor Latino, his identity as a young, Muslim, immigrant New Yorker proved “close enough” to gain trust in those communities.

If Mamdani’s message laid the groundwork for record turnout, it was an unusually disciplined field operation that brought the effort to fruition. New York’s progressive Left has rarely, if ever, assembled a machine of this scale or precision. In the Bronx, the city’s Latino-majority borough, that apparatus delivered one of Mamdani’s most decisive gains.

Only months earlier in the June primary, the borough had been solidly in Cuomo’s column, handing him an 18-point margin. But from mid-September onward, more than 1,900 members of 32BJ SEIU — a union with deep roots among Latino and black workers — joined the campaign’s canvassing corps. Together ,they knocked on 45,000 doors and placed more than 90,000 phone calls, transforming a once-unthinkable upset into a plausible path to victory.

And it wasn’t just 32BJ. By autumn, nearly every major union in the city — the Hotel and Gaming Trades Council, 1199SEIU Healthcare Workers, the United Federation of Teachers union, and more — had fallen in line behind Mamdani, creating a coalition of unprecedented breadth for a progressive campaign. This backing did more than mobilise votes: it sent a clear signal to black and Hispanic New Yorkers that Mamdani was a candidate who understood and represented their interests.

It’s important to note that Mamdani’s large margins with Latino and black New Yorkers do not make those communities “socialist”. Rather, their support signals a profound alienation from local politics, a sense of being unheard on issues such as rent, wages, transit, and groceries. They rewarded the first campaign that spoke directly to those concerns, in their language and on their streets.

Whether Mamdani can convert the trust vested in him into tangible relief, or partially implement his proposals without jeopardising the city’s long-term fiscal health, remains an open question. The real test will be whether he can deliver on those promises without breaking the city in the process.