Buffalo Bills executives started looking east a decade ago, conscious that the small market couldn't sustain an NFL franchise unless it expanded the fan base to Rochester.

That helped, but it wasn't enough.

"We dried up that market," owner Ralph Wilson said. "We turned over every stone."

So the Bills shifted their gaze north, crossing not just city lines but international borders. Wilson believes that the franchise's increased success at attracting Canadian fans is critical to its continued viability.

For NFL teams near Canada and Mexico, there are opportunities to augment not only game attendance, but merchandise sales, broadcasting revenues and corporate sponsorships.

Bills ticket sales in Canada are up 18 percent this season, Wilson said, boosted by the greater parity between the U.S. and Canadian dollars.

About 100 miles away, the Toronto metropolitan area has 4.68 million people — compared with 1.15 million in the Buffalo area. Toronto especially boasts many affluent consumers willing to buy tickets, Wilson said.

"It's no secret that western New York is declining in population and businesses," he said.

For clubs close to Mexico, marketing across the border goes hand in hand with appealing to burgeoning Hispanic communities in their own cities.

"They get almost a double benefit," said Mark Waller, the NFL's senior vice president of marketing. "They grow the fan base in the local market. At the same time, they build a second fan base in the international market."

So many people travel back and forth between the U.S. and Mexico and have family and friends in both places that when a resident of either country starts rooting for an NFL team, it can resonate across the border.

"They start communicating, visiting, coming back wearing Dallas Cowboys shirts and talking about them," Waller said.

The ability to reach the Hispanic community makes clubs more attractive to corporations seeking to connect with that growing market. Coors emphasized that desire when the company and the Chargers redid their sponsorship agreement two years ago, said Jim Steeg, the Chargers' chief operating officer.

Before the Houston Texans played their first game in 2002, the franchise formed a Hispanic advisory board, team president Jamey Rootes said.

"It's impossible to ignore the buying power of that group," Rootes said. "It's large, and it's young, and it's getting bigger every day."

As a six-year-old franchise seeking its first winning season, Houston faces obstacles in building popularity in Mexico despite its proximity. Longtime success, more than geography, has dictated which franchises have the most fans there.

The Cowboys and Pittsburgh Steelers enjoy the largest followings, said Geraldina Gonzalez-Soberanes, NFL Mexico's senior manager for sponsorships and public relations. The passion for the clubs is often passed from one generation to the next.

"Teams that get seen on TV, that's one way of fans connecting with you, and those are the ones performing the best on the field," Rootes said.

Five games a week air live in Mexico. Fans can purchase a satellite package to see the rest.

Steeg would like to see the NFL eventually regionalize its TV coverage in Mexico as it does in the U.S. That would allow Chargers fans in Tijuana and other parts of Baja California to catch all the team's contests in Spanish. They are able to listen to games on the radio in Spanish.

The Chargers enjoy the added benefit of third-year defensive end Luis Castillo, who is of Dominican descent and has his own weekly show on Spanish radio.

The Cowboys' 15 Spanish radio markets include Mexico City.

To engage fans, there's nothing like attending a game, Waller said. The Seattle Seahawks have about 1,000 season ticket-holders from Canada, said chief operating officer John Rizzardini. It's about a 2 1/2-hour drive from Vancouver to Seattle.

Canada has its own football league, of course, but the NFL's Waller said that as the CFL's popularity grows, so does the appeal of the American game.

"These are football fans," he said.

Football is the second most-watched sport in Mexico behind soccer, Gonzalez-Soberanes said. The NFL doesn't expect to overtake soccer in popularity, but it doesn't have to.

"From a marketer's perspective," she said, "we can live together."