“You have to pick a side so you can get into it,” Jones said in a telephone interview. “There will be yelling and screaming, I’m sure.”

She is a longtime Broncos fan who has never attended a game. Her boyfriend, Dave Welchert, who bought the Manning jersey for her in Boise, about three hours west of Arco, will back the Seahawks.

Image Debbie Jones, a bartender at Arco’s Sawtooth Club, expected a Super Bowl crowd of about 40, but it was unclear where the loyalties would fall. Credit... Jim Urquhart for The New York Times

Jones is hardly the only Idahoan who has been consulting maps and fiddling with a smartphone to chart the Broncos-Seahawks divide. That is mostly because of the scale of the game, but also because this state is in a bit of a football lull.

Idaho State and the University of Idaho have gone a combined 26-92 in the last five seasons. That has left the spotlight to Boise State, which posted Bowl Championship Series victories in the 2006 and 2009 seasons. But last year, those Broncos seemingly lost every close game in finishing 8-4, lost Coach Chris Petersen to the University of Washington, and lost the Hawaii Bowl under an interim coach after their starting quarterback was sent home early for disciplinary reasons.