NEW BRIGHTON — Residents of a Minnesota county facing a local sales tax hike to help build a new, billion-dollar NFL stadium spoke out overwhelmingly Wednesday in favor of letting them vote on the plan.

Most of the dozens who testified at a public hearing of the Ramsey County Charter Commission held near the suburban stadium site opposed the stadium tax proposal. The obscure panel holds the power to throw a major obstacle into the Vikings’ stadium dreams.

The commission could call a public vote on the proposed half-cent county sales tax to pay for a portion of the $1 billion stadium, which stadium supporters fear voters would reject and threaten the Vikings’ continued presence in Minnesota.

But those demanding a public vote outnumbered stadium supporters by a more than two-to-one margin at the hearing, though supporters balanced it out some toward the meeting’s end when commissioners allowed non-Ramsey County residents to speak. Many tax foes said they were Vikings fans but don’t believe scarce county resources should subsidize a privately held team.

“Ramsey County is having trouble filling potholes and keeping their libraries open,” said Bob Thayer, a resident of St. Paul, the county seat. He said a sales tax seemed a particularly unfair way to fund a stadium: “The people who have the smallest chance of attending a Vikings game are going to give the biggest percent of their income to pay this tax,” he said.

Another public hearing is scheduled for October, and the charter commission is likely to decide whether to hold the vote at that meeting. As proposed, the amendment would ask voters: “Shall Ramsey County be prohibited from using any revenues, including those raised by taxes or bonding, to fund or assist in funding a Major League Baseball or National Football League sports team or stadium.”

The vote likely wouldn’t occur until November 2012. Stadium supporters say that delay — and the likelihood that tax-averse voters would defeat the tax — would together deal the proposal a fatal blow. The Vikings’ Metrodome lease runs out at the end of the current season, and repeated statements by team officials that that nearly 30-year-old venue is no longer sufficiently profitable have raised fears that team could be wooed to relocate to Los Angeles, currently in aggressive pursuit of a new NFL franchise.

“If we wait nine months from the end of the season to vote, we may not have a team to vote on,” said Diggz Garza, a St. Paul resident. “If there’s no team and they leave, then I guess we all lose.”

The proposed 0.5 percent sales tax hike in Ramsey County would raise the county’s proposed $350 million share of construction on the $1.1 billion stadium proposal, with the state contributing $300 million through a package of sales taxes on sports memorabilia and other, mostly game-related spending. The team would contribute the rest, an unspecified amount likely to exceed $400 million.

Supporters of the stadium project would ask the Republican-controlled Legislature would override the public vote provision, as they did when Hennepin County bypassed a referendum on its own sales tax increase to help build Target Field for the Minnesota Twins. Vikings officials, who did not speak at the public hearing, have said they simply want the same treatment as the Twins.

But any referendum exemption granted by the Legislature is likely to be challenged in court. In addition, influential state lawmakers including House Speaker Kurt Zellers and Senate Majority Leader Amy Koch recently came out in favor of a Ramsey County vote on any tax hike.

Numerous county residents said it was unfair that they should bear a bigger financial burden in order to build a stadium for a team that calls the whole state home.

“This team as far as I know is not the Ramsey County Vikings,” said Dick Houck, a Roseville resident. “It’s the Minnesota Vikings.”