While Mayor Greg Ballard and his team plan to announce today their intent to bid for the 2012 Super Bowl, sources within the league said Indianapolis Colts’ owner Jim Irsay will be the determining factor.

“They could be the Emerald City, and it still comes down to one thing,” said an executive for a West Coast team. “Whether the other NFL owners want to do this for Jim Irsay. It’s not unanimous, but a number of owners think he deserves this.”

But it’s more than a popularity contest.

“This can get pretty complicated,” said the West Coast executive. “There’s a lot of ‘I’ll scratch your back you scratch mine,’ mentality here on a number of levels. Back-room deals and under-the-table handshakes? You bet.”

Marc Ganis, president of Sportscorp. Ltd., a Chicago-firm that advises a number of NFL teams on business operations, thinks Irsay’s clout among the other 31 team owners is rising.

“The weather in Indianapolis will always be a problem, but I think it will come to a point where the NFL owners will say, “Hey, there’s a reason we’re doing this,’” Ganis said. “And that reason is to pay back Jim Irsay for what he’s done for the league.”

Houston and Glendale, Ariz. are also expected to bid for the 2012 Super Bowl.

Do you think Irsay has the clout to bring the big game home?