Il Nuovo Postiglione - Mamdani-backed leftist candidates win New York Democratic primaries

While the results position Mamdani, 34, as something of a kingmaker in the solidly Democratic Big Apple, it remains to be seen to what extent his star power will translate outside of the city.

Mamdani's improbable rise highlights the Democratic Party's debate over a centrist or a leftist future, a flashpoint ahead of November's midterm elections.

"This is a battle between the establishment and this insurgency," political analyst and former Obama administration official Van Jones told CNN.

"And the roof is collapsing on the Democratic Party establishment," he said. "This is no longer a movement -- this is a movement and a machine at the same time."

Mamdani told the media Wednesday it was "essential" for the future to go beyond mere opposition to US President Donald Trump's "cruelty."

Highlighting the party's disunity, Democratic Pennsylvania Senator John Fetterman called the results "a banner night, you know, for the dirtbag left in New York."

- Democratic Socialists -

Brad Lander, who served as the comptroller for the previous mayor, defeated two-term incumbent Daniel Goldman in New York's 10th Congressional District, following a campaign focused on the Middle East war.

Lander called for an end to US military aid to Israel, while Goldman was backed by pro-Israel groups, including the American Israel Public Affairs Committee (AIPAC).

Adriano Espillat lost his bid for re-election to Darializa Avila Chevalier, a member of Mamdani's Democratic Socialists of America (DSA) party, in the 13th Congressional District.

Avila Chevalier, who once helped organize pro-Palestinian protests at Columbia University, has never held public office.

Another Mamdani-backed candidate, Claire Valdez, defeated Antonio Reynoso for outgoing Nydia Velazquez's seat.

Former president John F. Kennedy's grandson Jack Schlossberg lost his bid to replace longtime representative Jerry Nadler, who is retiring.

Schlossberg, 32, is seen as a progressive on the left of the Democratic Party and has vocally called for it to change.

He lost to Micah Lasher, a state assemblyman endorsed by Nadler. Mamdani had not backed any candidates in that race.

In reaction to the results, Trump posted on social media that the United States would "never be a communist country!"

Trump repeatedly labeled Mamdani a communist during the mayoral race.

- 'Build a movement' -

Political analyst Lincoln Mitchell said that "Mamdani and his allies are trying to build a movement."

"For a long time, they were told that candidates too far to the left could not be elected because they wouldn’t be able to win," Mitchell wrote. "But if they succeed now, that argument will no longer hold. That’s what is really at stake right now."

Mamdani, who took office in January, campaigned on lowering the cost of living. Since then, he has made progress on initiatives including free early childhood care and the opening of low-cost municipal supermarkets.

A decision on freezing certain regulated rents is expected soon, though the issue of free bus travel -- a major Mamdani campaign promise -- has stalled.

S.Maiolo--INP