In the multiyear fight between the global home-sharing conglomerate Airbnb and a relatively small union representing hotel workers in New York City, Airbnb’s string of losses has iced the company out of the city’s lucrative short-term rental market.

Now, with over a million tourists expected to flood the region for the World Cup tournament, Airbnb, an $84 billion company, has rekindled its fight to gain a foothold in the city. And central to its multipronged strategy are Black church leaders and property owners — a key voting bloc in New York — who say that they deserve the chance to make extra cash.

The company has hosted town halls and listening sessions in Harlem; Bedford-Stuyvesant, Brooklyn; and Jamaica, Queens — neighborhoods where Black homeowners are a significant force — to bolster support for proposed City Council legislation that would loosen regulations on short-term rentals. It gained the backing of influential Black pastors, including the Rev. Al Sharpton, who met with the City Council speaker, Julie Menin, to argue that allowing more of such rentals would benefit Black homeowners.

“We have always been supportive of the hotel workers’ union, but there is, in this particular case, unintended consequences, and that is Black homeowners,” Mr. Sharpton said in an interview. “Who are we protecting when the hotels are not sold out and people cannot rent rooms in their homes right there in Southeast Queens?”

For years, New York politicians have severely restricted the short-term rental company’s growth through at least four pieces of legislation and local enforcement activity. The union, the Hotel and Gaming Trades Council, has capitalized on its mighty political influence to keep Airbnb at bay. Under state law, short-term rentals in New York for less than 30 days are illegal, unless the host is present at the time of the rental.

And Airbnb’s nearly $900,000 lobbying effort for more favorable local legislation has failed in the face of politicians who cite the company’s impact on the rental market — but also are more concerned about running afoul of the savvy hotel workers’ union than enjoying the largess of a well-heeled corporation.

Chief among them is New York City’s mayor, Zohran Mamdani, who fought off Airbnb’s digital ad campaign attacking him during last year’s primary race — even though he was not endorsed by the hotel workers’ union.

Mr. Mamdani, an avid soccer fan, has touted the World Cup’s economic potential for the city. But the mayor declined to heed a request aligned with the company’s goals to roll back short-term rental regulations during the tournament.

His stance — along with the proposal he floated and then backed away from to raise property taxes, which angered some Black homeowners — could exacerbate tensions between him and that Democratic constituency.

In a statement, Joe Calvello, a spokesman for Mr. Mamdani, said that the World Cup should not create an opening for changes to housing policy and that the mayor supports regulating short-term rentals to stave off encroachment from the real estate industry.

“Homes should be for New Yorkers, not investment opportunities for predatory actors looking to cash in,” he said. “The mayor continues to oppose efforts to weaken these laws at the behest of corporate interests.”

To counter Airbnb’s appeal to Black New Yorkers, the hotel workers’ union has also sought out Black pastors to denounce the home-sharing company.

“Short-term rentals are driving up housing costs and contributing to displacement in Black communities that have already endured generations of disinvestment,” the Rev. Robert Waterman, lead pastor of a church in Brooklyn and president of the African American Clergy and Elected Officials organization, said in a statement.

In an interview, he added that he was approached to back Airbnb, but would not until the company or its allies provide more assurances that the company’s presence would not harm Black communities.

Corporations seeking to make political headway have relied on influential Black leaders in the past, as with a 2023 proposed ban on menthol cigarettes and before that, a proposed ban on the sale of fur products. But Airbnb’s fight comes against the backdrop of an enduring debate over how to keep longtime Black New Yorkers economically stable enough to remain in the city as rising prices and gentrification fuel their exodus.

On May 1, a coalition of more than a dozen Black religious leaders penned a letter to Ms. Menin that called reforms to short-term rental properties “a crucial financial lifeline for Black homeowners.” (Ms. Menin won her leadership post with the backing of the hotel workers’ union and remains closely aligned with it. Through a spokesman, she declined to comment on her meeting with Mr. Sharpton.)

Airbnb has further tried to ingratiate itself into the city’s civic scene through marquee events like the Way to Win Gala, which it paid several hundred thousand dollars to co-sponsor last week, according to someone involved in the soiree. A week earlier, it announced plans to give away 1,000 free tickets to the World Cup at an event for young soccer players in Queens. And on Friday, it opened a new soccer pitch in the Bronx.

The City Council bill to loosen short-term rental restrictions has only four sponsors, and in the unlikely event it is passed, it would not take effect for six months — making it irrelevant for any hope Airbnb has of breaking into the New York market in time for the World Cup.

The company is pushing for it anyway, and plans to maintain its presence in the city as the tournament takes place.

Nathan Rotman, Airbnb’s director of policy strategy, said the city will host more large-scale events that lure tourists — and provide more chances to demonstrate the company’s reach.

“There will always be something wonderful happening here,” he said. “And we want to make sure that the homeowners have those opportunities moving forward, whether it’s for events or just at a time of financial need.”

In turn, the union has mobilized its own forces.

It has teamed up with the Legal Aid Society of New York and housing advocates, who have published a raft of opinion pieces raising concerns about Airbnb, and it has held clinics addressing problems voiced by homeowners who support the short-term rental company.

The union has also formed a coalition with other labor groups and advocates ahead of the World Cup to address potential exploitation around housing and workers.

“The affordable housing crisis we face will be solved by creating long lasting affordability and generational homeownership opportunities — not short-term gimmicks that benefit tech billionaires at the expense of already marginalized communities,” the hotel workers’ union president, Rich Maroko, said in a statement.

Despite its relatively small membership, the union has long been revered and feared among New York politicians. It routinely turns out big rallies and spends big money for candidates it supports, while working ferociously against those it views as opponents.

But some of those efforts have caused blowback. Several of Airbnb’s Black allies also have taken issue with the union’s advertising, pointing to an attack ad that claims Airbnb will not check customers’ criminal history and uses the image of a man with dark skin and a hoodie.

The hotels also raise an economic reason to oppose Airbnb’s efforts: Early data suggests that the World Cup is unlikely to provide the boost hotels were expecting, despite projections that tourists will spend $1.8 billion, according to New York City Tourism and Conventions.

Vijay Dandapani, who runs the Hotel Association of New York City, said that hotels in the city have experienced a 10 percent bump in revenue based on present bookings related to the World Cup. But they expected more. He blamed the slower-than-anticipated World Cup bump on volatile energy prices, high tournament costs, airline troubles and what he called “draconian” federal visa policies.

“The hotel industry is still struggling post-Covid,” Mr. Dandapani said.

Asked why Airbnb would be spending so much time and money trying to win over politicians who are usually beholden to the union, Mr. Dandapani replied, “This is their model; they have a lot of money and they keep at it.”