NEW YORK CITY – The sky over City Hall was gray and ominous as American Postal Workers Union leader Jonathan Smith fittingly declared, “There is a storm a brewin’,” to whoops and cheers.

No, it wasn’t the rain beginning to fall on lower Manhattan. It was “Hurricane Bernie,” he boomed, “taking everything in its way.”

Roughly 50 supporters of the Vermont senator braved the inclement weather here Wednesday afternoon to file legally required petitions ahead of the New York Primary on April 19. Technically, they were delivering the requisite 5,000 signatures from Congressional Districts 5 through 15 to put a slate of delegates supporting Sanders on the primary ballot. But the real achievement they were celebrating was that, statewide, Sanders volunteers had managed to collect 85,000 signatures – 80,000 more than necessary – to put him on the primary ballot as a candidate for the Democratic nomination.

Arthur Schwartz, a lawyer for the Sanders campaign, claimed “not a single paid petitioner” was used to collect the signatures. “They did it as a labor of love,” he said.

A spokesman for Hillary Clinton did not return MSNBC’s request for comment on how many signatures her campaign was able to collect in New York as of this publication.

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Wednesday’s announcement marked the latest bit of posturing in a growing challenge to the idea that Clinton will inevitably be the Democratic nominee. With her record as a New York senator and Brooklyn-based national headquarters, Clinton has the backing of virtually the entire state Democratic establishment – including Gov. Andrew Cuomo, Sens. Chuck Schumer and Kirsten Gillibrand, and Mayor Bill de Blasio. But Sanders, a Brooklyn native who never lost his thick accent, has his fair share of New York support as well.

“I can smell a victory in the New York primary,” shouted one Sanders supporter.

“Bern, baby Bern, it’s the people’s inferno,” sang another.

Almost every speaker pointed to Monday night’s Iowa caucuses, which Clinton won by just a hair, as evidence that Sanders has a legitimate shot at the nomination.

“If you don’t feel the Bern after Iowa, there’s something wrong with you,” said Smith of the Postal union.

“I think we proved in Iowa that we have a really good chance of winning,” said Rafael Espinal, a councilman from Brooklyn. “A lot of Latinos, a lot of African Americans are feeling the Bern.”

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Several speakers attacked Clinton for not being sufficiently progressive over the years and seeming to shift her positions based on political expediency. Mary Fitzgerald, a pediatric nurse and member of the New York State Nurses Association, called Clinton a “Johnny-come-lately” on health care for all. Former state Sen. Tom Duane, who was the only openly gay member of the New York Senate, appeared to take a veiled swipe at Clinton’s relatively late support for marriage equality, saying “Some candidates, they have to evolve… But you know who was already there? Bernie Sanders.” Allen Roskoff, president of the Jim Owles Democratic Club, was more explicit: “She is the last prominent Democrat to support marriage equality. We have to remember who our friends are.”

view photo essay The presidential campaign: Bernie Sanders The self-described democratic socialist is known for pushing change on income inequality, college affordability and criminal justice reform.

“He’s not bought out by anyone, he’s not taking corporate money, he doesn’t have a super PAC, which is huge,” said 23-year-old Rachel Brown-Mcloughlin. She said she would not support Clinton, whose super PAC has raised millions from Wall Street, if she became the nominee. “I’m basically Bernie all the way. Bernie or bust.”

On the walk down Broadway to drop off the petitions at the Board of Elections, 27-year-old Steven Abreu would repeatedly press his sign against the windows of banks and shout, “Feel the Bern.” He said some people would snicker and call him a socialist as he stood at LIRR train stations to collect signatures for the ballot. (He personally got 500.) But what really made the process difficult was the weather.

“It was a lot of standing outside on train stations, in the rain, after the snowstorm, bundled up with four layers, feet warmers, hand warmers. The whole nine yards,” said Abreu, now soaking wet from the rain. “This is nothing.”