The northern campaign for the proposed football stadium has begun as officials Wednesday traveled to Reno to float a possible training/practice facility for the Raiders, sources confirmed.

This comes as a timeline for approving the stadium — a three-tiered process — means a special session would be needed before the end of the year, and northern votes would be required to approve hundreds of millions in room taxes for the southern project. A Reno component might sway some of those lawmakers.

I’ve also learned that Gov. Brian Sandoval is unlikely to call a special session before the election, fearing the impact on legislative contests, and also that developers may have to come up with a backup site to the Bali Hai golf course because of potential FAA questions. Sources also say the governor and a majority of a stadium-screening committee are unlikely to allow the developers to have their desired $750 million in public money, with $500 million perhaps the minimum.

Raiders and Las Vegas Sands representatives held meetings in Reno on Wednesday, a move that surely is partly designed to shore up northern legislative support should that special session be called later this year. (Two-thirds of the Assembly and Senate would be needed.)

Sources confirmed that the lobbying contingent is proposing the practice facility on either the University of Nevada, Reno campus or at a Reno rodeo venue. The substantive arguments bolster the political motivation: Cooler than Las Vegas in the summer and proximity to the Oakland fan base.

“Reno seems like the right place to do it,” one source familiar with the stadium plans told me.

The move is another sign that the Raiders/Sands consortium is trying to cover all the bases. The plan would need to pass a stadium committee, then the Legislature and two-thirds of the NFL owners when they meet next January. (I reached out to the Sands folks, but to no avail.)

A special session could be called before the election, but the governor prefers to wait until afterward. Remember that the special session for Tesla two years ago was done in September, two months before the election. If it were called after the stadium committee were to approve the project in September, that would prevent incumbents from raising money for a substantial period close to the balloting and possibly affect election outcomes.

A November session, though, would leave time for developers to get their presentation ready for the owners, who meet in January. If they were to miss that owners confab, they would have to wait another year, which would likely be the end of it.

Although the Bali Hai site, as I have reported, is the prime choice, it would have to meet FAA scrutiny. And that could be a lengthy process that would not be completed by the owners' meeting.

"Under federal law, developers must give the FAA the chance to review certain proposed structures to determine if they could pose a hazard to aircraft or navigation aids,” FAA Public Manager Ian Gregor said. “This includes any structure over 200 feet tall anywhere in the country, and shorter structures, too, depending on how close they are to airports. Any sports stadium near an airport would require FAA review.”

Gregor said the FAA already is reviewing one proposed stadium site on Tropican Avenue. The Bali Hai site, if the Sands could wrangle the lease on it from developer Billy Walters, is partly in a Runway Protection Zone, which bars all development. But much of it could be cleared by the FAA for a stadium, although the developers would have to dig down to meet the height restrictions not the land.

"The FAA's determination is only a recommendation; we don't have authority over local building decisions,” Gregor told me. “However, many local governments (including Clark County) have laws that preclude them from issuing building permits if the FAA issues a hazard determination.”

That’s why some believe a secondary site — such as one on Russell Road away from the airport and near Bali Hai or a Fertitta family-owned parcel around the Wild West casino — would have to be part of any NFL application. But that’s just one piece of the stadium puzzle, including northern buy-in, that stadium advocates would have to assemble in the next four months.