SANTA CLARA, Calif. — The timing couldn’t have been any better.
After years of turmoil and losing, the San Francisco 49ers, who face the Green Bay Packers in the N.F.C. Championship game on Sunday, are one victory from returning to Super Bowl. There is no better way to drive demand for tickets, jerseys and support from a business community with cash to burn.
And one more thing — the 49ers’ bonanza is happening as their longtime rivals, the Raiders, abandon the Bay Area for Las Vegas, leaving the 49ers to reign as the lone West Coast team between Seattle and Los Angeles and in prime position to annex the East Bay, which has for years been enemy territory clad in black-and-silver.
Making inroads into Raider nation won’t be easy. Raiders fans are among the most fiercely loyal in the N.F.L., and adopting the rival next door as their home team is not in their D.N.A. There were not many Brooklyn Dodgers fans who started rooting for the Yankees in 1958 either. Some fans will follow the team in Las Vegas, even flying there to see them play. Other Raiders fans may stop watching the N.F.L. entirely.
“You’re either a Raiders fan or Niners fan, but you’re never both,” said Wayne Deboe, the president of the Oakland Raiders Booster Club and a fan since the team’s inception in 1960.
Still, the 49ers ascendancy is likely to draw some fans who just want to watch a winner. The Bay Area is filled with transplants seeking Silicon Valley riches — and maybe a local team to root for. Younger fans, even those whose parents have a proclivity for silver and black, may latch onto the rising Niners, who are delicately trying to jump on a golden opportunity.
“We would never try to convert Raiders fans,” said Alex Chang, the chief marketing officer of the 49ers, before outlining what seemed like a pretty good plan to do just that. “It’s a multigenerational play here for people who are transplants or kids who are growing up here now and won’t have the Raiders.”
There will be an expansion of 49er charities in the East Bay. The franchise will invite more East Bay school children to its science and technology programs and expand its free flag football programs. The efforts are not necessarily designed to sell tickets, but represent a kind of soft-sell to bring residents in the entire Easy Bay closer to a team more associated with the city of San Francisco and the peninsula stretching down to San Jose.
Last year, about 60,000 school children from the region visited Levi’s Stadium. The 49ers also funded free flag football leagues for 3,000 boys and girls that were hosted by the Boys & Girls Club, Police Athletic League and city recreational programs there. Children who play in these leagues all receive a Niners reversible jersey. The team will also run one-time football clinics, often with 49ers, in the East Bay. The team intends to triple that number next season by working with those organizations in the East Bay.
“We want kids to be 49ers fans, but it’s not like we want someone not to be a Raiders fan,” said Hannah Gordon, the team’s chief administrative officer.
Sports leagues have tried in the past to create boundaries so that neighboring teams do not encroach on each other’s markets. In the N.F.L., a team’s territory was a 75-mile radius from its home city. Because San Francisco and Oakland are just 10 miles apart, the 49ers and Raiders have informally stayed out of their each other’s cities — no billboards, instance.
But the growth of social media has made lines on a map obsolete, and now the Raiders are gone altogether.
Winning the hearts of abandoned fans is not easy. The Mets were created in 1962 five years after the Brooklyn Dodgers and New York Giants moved to California. The Chargers, who abandoned San Diego three seasons ago, are struggling to gain traction in Los Angeles.
The Kansas City Chiefs have moved eastward across Missouri to St. Louis, which lost the Rams in 2016. Mark Donovan, the Chiefs president, said the team acknowledged that Rams fans may still be angry about the decision to move, but he said ticket sales and sponsorships from that part of the state are on the rise. There is a lot more Chiefs programming on local radio affiliates, too.
The Chiefs’ success — they play in their second consecutive A.F.C. title game on Sunday — has also won over skeptical Rams fans. Chiefs quarterback Patrick Mahomes and tight end Travis Kelce drew a big round of applause when they attended a Blues playoff game last year.
“I don’t think the rivalry between the teams was so bad that people wouldn’t root for the Chiefs,” said Randy Karraker, a talk-show host on 101 ESPN in St. Louis.
That may not be the case in the Bay Area, where the Raiders and 49ers have different identities dating back decades — the 49ers have long been the team of the elite, while the Raiders were the team of the working class. Still, success changes the calculus. Sales of 49ers merchandise have been the strongest in the East Bay — from San Leandro to Oakland to Fremont — this season, up 250 percent compared with last year, according to Fanatics, the largest online seller of licensed merchandise.
“The Bay Area is very provincial,” said Andy Dolich, who worked as a business executive for the Oakland A’s, Golden State Warriors, and, from 2007 to 2010, the 49ers. “But this Niners team has been able to jump the county barriers.”