Mike Golic Jr. expresses his enthusiasm in the possibilities for the Raiders if they move to Las Vegas. (1:04)

LAS VEGAS -- Backers of a proposed NFL stadium said they've whittled their list to two sites just west of the Las Vegas Strip and will refuse to accept any less than $750 million in public funding toward the project, which they hope will soon be home to the Oakland Raiders.

Representatives from Majestic Realty and the Las Vegas Sands casino company updated an oversight committee Thursday on their quest to build a 65,000-seat domed stadium, showing off their slick renderings of the proposed venue in a video with an edgy soundtrack. They said the price tag continues to rise and is now $1.9 billion, saying they'd walk away from the project if state lawmakers don't meet their minimum financial demand.

"Not to be difficult, but we're not negotiable," said Sands president Rob Goldstein, who spoke on behalf of billionaire casino mogul Sheldon Adelson and his family. "If we can't get 750, we respectfully thank you but we're going to move on."

The Raiders have made little progress securing a new stadium in the Oakland area and have committed to lining up $500 million toward building a new one in Las Vegas. Any team relocation needs the blessing of three-quarters of NFL owners, so developers are rushing to prepare their pitch by January, when the owners next meet.

Stadium supporters who presented a long list earlier this summer said Thursday that they've zeroed in on two land parcels south of the Mandalay Bay hotel complex. They've signed a preliminary agreement for their top candidate -- a 62-acre plot just west of Interstate 15 -- but also cited a secondary option at the Bali Hai Golf Club between the interstate and the Las Vegas Strip.

Early designs submitted by the Oakland Raiders to the Southern Nevada Tourism Infrastructure Committee for a Las Vegas-based stadium. Courtesy of MANICA Architecture

Public funding would come from an increase in a Las Vegas-area hotel room tax and potentially from a special taxation district around the stadium. Officials said the stadium itself would be publicly owned, while the private investors would be on the hook for cost overruns but could potentially reap returns from their investment.

Critics include the powerful Culinary Union, which represents hotel workers and argued that the NFL and the Sands can afford the project on their own.

"There's been a lot of conversation on why are we giving money to billionaires," said Steve Hill, chairman of the oversight committee and head of the Nevada Governor's Office of Economic Development. "The public is not making a contribution to a privately owned stadium."

Developers urged the committee to work quickly to recommend the project to state lawmakers, who must approve any tax hikes and authorize a stadium board to oversee its operations. Sands officials want a special legislative session in September and say delaying action could jeopardize the project, but some top lawmakers want to wait until after the November election so the project doesn't affect campaign fundraising or sway votes.

Stadium proponents also responded to concerns that the Raiders would move after the Las Vegas area invested in their venue, leaving taxpayers holding the bag. Team officials said they'd sign a lease that lasted as long as the debt -- 25 or 30 years -- and Sands officials said they'd hold the team accountable for the Adelson family's major investment.

"We'll be right there with you making sure [Raiders president] Marc Badain will die here," Goldstein said.