As athletes parade into London’s Olympic Stadium this Friday, Twitter Inc.’s Olympic hopes will play out in a spartan office in Boulder, Colo.

There, a handful of people will spend 20 hours a day to help corral millions of Twitter messages from Olympic athletes, their families, fans and NBC television personalities into a single page on Twitter.com.

witter’s Olympics hub, part of a partnership between the San Francisco company and Comcast Corp.’s CMCSA -2.52%NBCUniversal that will be announced as early as Monday, is one of the first times Twitter will serve as an official narrator for a live event. NBC will tout the website with on-air promotions and links to athlete interviews or video clips.

With the partnership, Twitter hopes to use the Olympics as a launch pad into a more sustainable business. Twitter, which allows people to post 140-character messages called tweets, has built up more than 140 million monthly users and has become a go-to resource for people to find news or to gab about “American Idol.”

But executives want the six-year-old service to find a larger audience, especially amid doubts about Twitter’s ability to become a serious money maker.

Research firm eMarketer Inc. estimates Twitter will generate $259.9 million from advertising this year—far less than Facebook Inc.’s FB -0.31% $3.15 billion in 2011 revenue. Wider adoption can help Twitter expand its ad business, justify its $8.4 billion valuation and eventually pave the way for an initial public offering.

As a result, Twitter’s Olympics bet is crucial. “This is a way for new users to sample Twitter,” said Chloe Sladden, Twitter’s vice president of media.

NBC said no money is changing hands in its Twitter partnership and that it won’t share in revenue from ads that Twitter is selling to Olympics sponsors for its Games website. Brands such as General Electric Co. GE -0.01% and Procter & Gamble Co. PG -0.61% already have bought ads on Twitter to promote their association with the Olympics.

Twitter declined to comment on the money it hopes to generate from the Games. P&G didn’t return a request for comment. GE said it expects “the 2012 Games to be a pinnacle of social activity.”

“There’s no way of knowing exactly how much advertisers will spend on Twitter during the Olympics, but there is no doubt they will be jockeying for ad space during some of the key events of the Games, when traffic on Twitter will explode,” eMarketer analyst Debra Aho Williamson said.

Twitter has prepared for the Games for months. The company has hosted dozens of sessions with athletes and national sports associations to pitch them on using its service. Twitter has courted companies to buy ads on Twitter to spread their Olympics marketing messages. The International Olympic Committee said well over 1,000 current and former Olympians are using Twitter or Facebook for the Games.

Advertisers said Twitter has pushed itself to them as an effective marketing vehicle. Athletes and Olympics organizations said that ever since the 2010 Winter Olympics in Vancouver, British Columbia, there has been an explosion of athletes embracing Twitter to talk to fans and occasionally trash talk to rivals.

During the Games, Twitter will use its Olympics events page to highlight insiders’ views, and to encourage people to watch NBC’s on-air and online coverage. Twitter will embed its own staffer with NBC’s social media team in London to ensure fresh news, interviews and links to TV highlights will show up on Twitter. The Olympics “hashtag”—a way for Twitter to organize tweets about a single topic—will pop up on screen during television coverage, NBC said.

Twitter will be visible offline as well, not just on TV or online. The London Eye, a giant Ferris wheel dominating the skyline, will light up each night based on the sentiment of Olympic tweets, although Twitter said that isn’t part of its campaign.

Some research shows social media is fueling viewership of live TV, as people want to interact over Kobe Bryant’s dunk or Angelina Jolie’s Oscar dress. Social-media analysis firm Trendrr said Twitter accounted for an average of three quarters of the “social activity” around broadcast TV programs in the first quarter of this year, vs. 16% for Facebook. For sports or other major televised events, Trendrr found Twitter has a near-lock on digital conversations.

Twitter believes the Olympics partnership with NBC is a chance to cement that status. It means “Twitter is really where the party is,” Ms. Sladden said.

Facebook, which has a similar events page launched in conjunction with NBC, isn’t selling ads there tied to the Olympics. Facebook declined to comment.

It is unclear if the interests of Twitter and NBC will always align during the Games. NBC plans to contain highlight clips and other Olympics video on its own websites and mobile applications, which won’t necessarily appear on other digital services. Twitter also may tread on NBC’s turf by essentially programming the Olympics on its events page.

Twitter and NBC said they aren’t in competition. NBC’s Olympics president, Gary Zenkel, said Olympics coverage anywhere helps NBC by stoking viewer interest.

“We’re quite aware of and comfortable with the fact that [Twitter] is a place where news will surface, and in some cases the news will be made,” said Mr. Zenkel. “At the end of the day, the only place you can watch the Olympics—which is what people crave—is NBC.”

Meanwhile, Ms. Sladden said she would be in Twitter’s San Francisco headquarters during the Games, closely watching the coverage. “I’ll be consuming tweets and tweeting—and maybe trying to get some work done,” Ms. Sladden said.