ST. PAUL — Gov. Mark Dayton, political leaders and the Minnesota Vikings unveiled a proposal Thursday to build a $975 million stadium for the team in downtown Minneapolis and called for quick action on the plan before the Legislature adjourns this spring.

The plan would put the new building nearly on top of the current Metrodome site. It calls for $398 million from the state, $150 million from the city and $427 million from the Vikings for upfront construction costs.

The state’s share would come from an expansion of pulltab gambling games to add an electronic version, while Minneapolis’ share would come from redirecting existing convention center and hospitality taxes.

“Now the real work begins,” Dayton said.

The plan was rolled out at a Capitol news conference with Dayton joined by top legislators and team owners Zygi and Mark Wilf. Dayton has pressed for action on a new Vikings stadium for months, fearful that the team may leave the state without it as the Lakers did long ago.

“This is an exciting day, because the dream of keeping the Minnesota Vikings here for generations to come is close at hand,” Vikings owner Zygi Wilf said.

Still, the Vikings’ Metrodome lease has expired, and though they will play next season there, their future in the state is not assured.

Dayton and political leaders have touted the project as a “people’s stadium,” to be used by colleges and high schools and for special events. Dayton said it would create jobs, too: as many as 8,000 construction jobs, 5,000 related jobs for suppliers and others, and 2,000 permanent jobs after that.

Supporters said the Vikings’ share of the stadium costs would amount to just over half because the team would commit to paying some operational costs over time. But much of the money for those costs would likely come from stadium revenues earmarked for the team, and the proposal outlined Thursday gave no details on revenue distributions.

The Vikings have lagged at the bottom of the league in annual revenue in recent years at the Metrodome, which opened in 1982 as the quintessential multipurpose facility. The dome was always functional over fancy and despite excellent sight lines for fans in most seats for football games, the concourses are cramped, the decor is drab and the amenities are outdated. The Vikings have been asking for public subsidies for a new stadium for more than a decade, citing their need to be sufficiently profitable in the annual $10 billion business that is the NFL. A snowstorm that caused a roof collapse on Dec. 12, 2010, put that plea in sharper focus.

But the economic downturn in recent years put the team’s quest in deeper trouble, too, particularly after Republicans gained control of the Minnesota Legislature at the start of 2011, forcing stadium supporters to abandon any financing schemes based on state or local tax increases.

Several different proposals and deals have fallen apart over the years. Just in the last few months, a suburban project in Arden Hills was scuttled by political complications and limited funding options. Another plan to build on the west end of downtown Minneapolis was derailed after leadership at a Catholic church balked at the potential of nearby construction and disrupted Sunday mornings.

That left the current Metrodome site, on the east edge of downtown.

Any stadium deal that involves money from Minneapolis faces a big hurdle to clear with the city council. While Mayor R.T. Rybak and Council President Barbara Johnson have been enthusiastic supporters, other members have remained skeptical about diverting city resources to a privately owned sports franchise.

Council members cite a provision, approved by voters in 1997, that prohibits the city spending more than $10 million on a pro sports project unless it’s approved by a public vote. For the new plan to work, that provision will likely have to be overridden by the Legislature since a majority of council members had previously been on the record in support of it.

If the deal can survive Minneapolis politics, that still leaves a heavy lift to get majority support in the state House and Senate. A stadium bill would likely be vetted by multiple committees, some of which are chaired by tax and spending skeptics. GOP leaders, particularly House Speaker Kurt Zellers, have refused to assign the same urgency to a stadium vote this year as the project’s supporters would like.

Last month, Dayton criticized unidentified lawmakers for what he said was a reluctance to vote on a stadium bill this year and a desire to wait until after this fall’s election. Dayton encouraged a vote in the current session, which must end by April 30, but nothing requires lawmakers to act this year.

The NFL would also have to approve any stadium deal since part of the Vikings’ share would likely come from a league funding program to help build new facilities around the NFL.

For years, Vikings fans have pondered the threat of losing their beloved, bedeviling team, which began in 1961, if the Metrodome isn’t eventually replaced. Minnesota sports fans know all about losing professional franchises; the Lakers moved to Los Angeles in the 1950s and became an NBA powerhouse. The NHL’s North Stars left for Dallas in 1993.

For now, though, the threat of the Vikings actually leaving is a mild one. The team has refused to acknowledge interest in moving while confirming previous contact from interested groups including developers in Los Angeles. Stadium projects there are planned but not under way without the promise of a new team; the NFL’s deadline for relocation application already passed for 2012, and Commissioner Roger Goodell recently stressed the league’s desire to put an expansion team in Los Angeles rather than one in an existing market.