Even as the Oakland Raiders are packing their suitcases, East Bay officials and others are deep in negotiations with a money management outfit that just might have the financial muscle to compete with Las Vegas’ offer of $750 million in public cash for a new stadium.

There’s one person who’s not at the table, however: Raiders boss Mark Davis. He’s made it clear he’s no longer negotiating to keep the team in Oakland.

Davis told USA Today last week that he had made a commitment to Nevada Gov. Brian Sandoval — that “if they came through with the funding that they were talking about, that I would do everything possible to get there. I was not using it as leverage.”

Nevada did its part: Last week, Sandoval signed a measure allowing Las Vegas to raise $750 million in hotel tax revenue and hand it over to billionaire Sheldon Adelson to build a $1.9 billion stadium that would house the Raiders.

“I’ve never played cities against each other,” Davis said.

What that means, said Stanford University sports economist Roger Noll, is that “the play is at the league now.”

The upshot: East Bay officials will have to convince at least nine of Davis’ 31 fellow NFL team owners that Oakland has a viable stadium plan and that, as a result, the league should tell the Raiders to stay put.

Apparently, Oakland’s hopes rest with the Fortress Investment Group, a money management firm in San Francisco that boasts $72.2 billion in assets. Multiple sources tell us that Fortress is the potential money behind a group led by ex-NFL stars Ronnie Lott and Rodney Peete that is trying to put together a Raiders stadium deal here.

Its principal and co-chairman is Peter Briger Jr. of Atherton, whose personal fortune has been put at more than $1 billion. Fortress’ co-chair is Wesley Edens, part owner of the NBA’s Milwaukee Bucks, which broke ground this year on a $500 million downtown arena.

A spokesman for Fortress declined to comment.

One public official involved in the East Bay negotiations, who spoke on condition of anonymity because of the sensitivity of the talks, said the hope is that Lott can persuade Davis to sit down with his group if it can get control of the Coliseum site from the Oakland-Alameda County Coliseum Authority. The Coliseum site is where a new stadium would be built, and the thinking is that Lott’s group would have credibility with the Raiders owner if it actually had the land.

A deal with Fortress would also add oomph to the Lott effort — but there’s no guarantee that’s going to happen.

One of the people trying to bring it together is Gregg Perloff of Another Planet Entertainment, the San Francisco concert production company that runs the annual Outside Lands festival. He’s joined forces with the Lott group, which presented an outline “term sheet” last week for acquiring and developing the Coliseum site to Oakland Assistant City Administrator Claudia Cappio.

Cappio has been shuttling back and forth between Oakland and Fortress’ downtown San Francisco offices. That’s where the main stadium talks have been held since Lott got tired of sneaking out of Oakland City Hall to avoid reporters.

“There is a great deal right now to be had with the Raiders,” Perloff said, though he declined to discuss any specifics.

“But it has come about late,” Perloff said. “Hopefully, not too late to save the situation.”

Sports economist Noll, for one, said keeping the Raiders will be a huge challenge. Oakland may be in the booming Bay Area, but the Coliseum site off the Nimitz Freeway doesn’t have the glitz and profit potential of downtown Las Vegas.

And the Lott group wants part ownership of the Raiders. Noll said it’s unlikely the NFL owners would force Davis to stay put at the cost of a chunk of his team.

“It would set a precedent that the other owners would not like to see possibly happen to them,” Noll said.

Among the other issues: How would the Coliseum authority go about handing over publicly owned land to a private entity like the Lott group? Who would pay off the outstanding $95 million debt from the Coliseum renovation that lured the Raiders back from Los Angeles in the 1990s, a burden now borne by taxpayers? And of course, what would happen to the Coliseum’s other tenant, the Oakland A’s?

We’ve also learned that the Oakland group doesn’t even have a project developer. An Atlanta financier, Egbert Perry, was dumped from the Lott group after he tried to make an end run and acquire the Coliseum site himself. Because he was hooked up with big-time local developer Seth Hamalian, founder of the Mission Bay Development Group, Hamalian is gone, too.

Put it all together, and one high-level source privy to the talks is skeptical that Fortress will be part of the deal — even calling it “highly unlikely.”

On the other hand, not all the financing details are in place for the Vegas stadium, either. It’s likely there will be more twists and turns to this story before NFL owners meet next in January, when a Vegas move might come up for a vote.

“We are working hard — we haven’t been sitting on our hands,” said Oakland City Councilman Larry Reid, a member of the Coliseum Authority board and a major cheerleader for the effort to keep the Raiders here.

The question is whether the East Bay will have a pen-and-paper plan by January that it can sell not just to the NFL, but to the taxpayers here at home.

S an Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX-TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or email matierandross@ sfchronicle.com. Twitter: @matierandross