Sunday's TCS New York City Marathon will draw more than 50,000 runners and wheelers, along with more than a million spectators to the streets of the Big Apple. An international event, the participants, their friends and families come from 125 countries, generating an economic windfall for the city that is estimated at about $350 million, according to a 2010 study done by the New York Road Runners club.
"It's an extraordinary moment for us economically. ... Our hospitality sector runs at full tilt this time of year, and it's great for jobs in the city, and its great for the economy," Mayor Bill de Blasio said at a press conference Thursday.
A big chunk of that windfall, $65 million, goes to the hotel industry, but it has competition in the form of Airbnb, the short-term, home-sharing site that has raised its profile this year with a sponsorship of the marathon.
"It's the perfect complement to the hotels, many of which are full," said Mary Wittenberg, CEO and president of New York Road Runners.
The decision to add Airbnb as a sponsor is not without controversy. The site has drawn criticism from officials like New York State Attorney General Eric Schneiderman, who claims the site allows many homeowners to operate illegal hotels.
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Wittenberg said it's unlikely that the sponsorship deal will have a significant effect on established hotels, which are the prime beneficiaries of the New York City Marathon, making an estimated $65 million from marathon weekend.
"Airbnb is just another option, and we're hoping to see more friends and family come and get more people involved in this," Wittenberg said.
The four-year deal names Airbnb as the race's "official hospitality sponsor." Signs for the privately held firm, which is valued at $10 billion, can be seen all along the 26.2 mile race course that winds through the city's five boroughs.
New York Road Runners said that the partnership focuses on New Yorkers serving as neighborhood ambassadors to the running community and lets runners experience the diversity of Manhattan and the surrounding boroughs.
"Many Airbnb hosts and guests are runners, and we're honored to have the chance to support this amazing event," Airbnb said in a statement to CNBC.
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For travelers looking for a last-minute booking in an already crowded city, Airbnb can be an economic alternative.
"We were looking for somewhere that had a kitchen and was close to the Central Park finish line," said Shane Holstein, a runner who traveled to New York from Perth, Australia. He found an Airbnb rental that provided him those amenities and proved cheaper than the hotels he looked at.
"We're going to watch the Jets play on Sunday and a Broadway show—things that we might not have ended up doing if we had to pay full price for a hotel," he said.
A majority of the city's 108,500 hotel rooms are sold out over marathon weekend, and according to tourism site NYCGO.com the average daily price for a hotel room in NYC was $290 in 2013. On Airbnb, lodgers can still rent a studio apartment on New York City's Upper East Side for $65 a night.
Airbnb declined to provide statistics on how many had signed up for apartments over this year's marathon weekend. It did say that more than 10,000 visitors stayed in Airbnb listings during last year's race, earning about a million dollars for city residents. The majority of the renters were foreign visitors, with 73 percent coming from 88 different countries.