The old immigrant organizations of north Chinatown are distancing themselves from the games, while leaders who represent a growing group of newer immigrants from the Fujian region of mainland China are publicly celebrating the games.

Hundreds of Fujianese are rallying for the Olympics in the week leading up to the games. At an event in Foley Square on August 2 and a parade on the Brooklyn Bridge on August 3, they sang Chinese songs, and chanted “Beijing will be perfect.”

Just days before those pro-Olympic rallies, the president of a 125-year-old, Taiwan-allied community organization, Justin Yu, said there was “nothing happening” to celebrate the Olympics among New York’s Chinese-Americans.

“They don’t want to be a part of it,” the vice president of a Fujianese group that organized the parade, Jimmy Cheng, said in response to Mr. Yu’s comment. “For the Olympics, he should be coming to me for celebrations. He should get together with the Fujianese.”

But international political allegiances have gotten in the way of such a joint event.

Mr. Yu’s organization, the Chinese Consolidated Benevolent Association — often referred to as the City Hall of Chinatown, or by its abbreviation, CCBA — has maintained a pro-Taiwan, anti-Communist stance since Mao Zedong’s takeover in 1949, according to its official literature.

“The mainland government, they’re Communists, and we don’t like that,” a 74-year-old business consultant who works for the association, Chan Ming Chien, said. “The new immigrants came from China in a happier time, so they like it more than I do.”

The CCBA has held no Olympic celebrations, nor have other large cultural organizations such as the Chinatown Partnership and the Chinese-American Planning Council.

In stark contrast, the Fujianese organizers of the rally and parade are openly pro-Beijing.

“The CCBA are old. They’re part of Taiwan. We are from Red China,” Mr. Cheng said.

“Most of our people are born in the People’s Republic of China, and that’s why they’re so close to it,” the president of another Fujianese organization, Kenneth Cheng, said. ‘We are celebrating because we want the world to know that China is important.”

In demographics, as well as political influence, the Fujianese community has grown rapidly in recent years. Since the 1980s, they have become the fastest-growing Chinese group in Chinatown.

For years, the Fujianese and the Cantonese-speaking “historical core” of Chinatown almost never mixed, according to the executive director of the Chinatown Partnership, Wellington Chen.

Subsequently, relations have cooled, “But it’s still basically two different economies,” Mr. Chen added.

Still, leaders on both sides say they are looking forward to watching the Olympics.

“Generally speaking, there’s obviously a lot of pride in the fact that, for the first time in history, the torch has been passed to China, and that’s a unanimous comment that people are saying,” Wellington Chen said.

One New York-born CCBA volunteer in his 20s, Karl Leung, said what matters is how long ago one’s family came to America. “If you look at a new immigrant, they might be rooting for China,” he said. “But I want to see LeBron James dunk on Yao Ming.”