With a weekend deadline fast approaching, the two sides in the Minnesota Orchestra dispute are talking intensely and confidentially.

But if there is progress, it has not been visible.

Meanwhile, sources say private efforts are underway to raise money that might help bring a contract settlement before Sept. 30. That is when Music Director Osmo Vänskä has said he needs the musicians rehearsing in order to prepare for Carnegie Hall concerts in early November.

Other sources have speculated about whether the state of Minnesota could find money to help reach a deal.

The orchestra’s board issued a statement Tuesday saying an offer given on Sept. 14 had expired Monday without a response from musicians.

A spokesman for the musicians would say only that both sides are still talking through mediator George Mitchell, a former U.S. Senate majority leader.

Details of the proposal that expired Monday were not released because they are part of the confidential process with Mitchell.

“Despite this current setback, the board remains optimistic,” said Richard Davis, chair of the negotiating team. “We expect to continue dialogue and use every day in the week ahead to seek a settlement.”

Musicians’ spokesman Blois Olson said the management proposal was essentially the same one that musicians have rejected several times.

Some board members are working outside of the negotiating team in search of a solution. Olson said Tuesday that musicians have met independently with board members, but he would not comment on those conversations.

Other sources, in the past week, have indicated that at least one key board member has called together leaders of corporate and private foundations to see whether enough one-time money could be raised to sweeten an offer to musicians.

The board’s official position is that the orchestra’s financial difficulties are systemic and that special funding — sometimes called bridge funding — merely kicks the problem down the road.

It is not unusual for arts organizations to make special appeals to donors, corporations and foundations to seek one-time funds to cover deficits. Aggressive fundraising in the summer of 2004 yielded $3.9 million to address a significant annual deficit. That, too, was a contract year.

The effort that now appears to be underway, however, is tied directly to the contract negotiations. It is unclear how the money might be used — to provide signing bonuses to musicians or to alleviate the Minnesota Orchestral Association’s financial pressure. No one will say how much money has been pledged.

State funding would be trickier, as one state official said, because favoring one organization over another could be perceived as unfair. Sue Gens, executive director of the Minnesota State Arts Board, said she has not been contacted by Gov. Mark Dayton.

“State funds are meant to be used for programs that benefit people through education and outreach — not for contract settlements,” Gens said.

She, too, wonders about the precedent of giving special money to one arts group and not to others.

“I don’t even know how to think about that,” Gens said.

Rep. Phyllis Kahn, the Minneapolis DFLer who leads the House Legacy Committee, is less concerned about what she calls the rigidity of the State Arts Board funds.

“I think the state should take a hand in it,” Kahn said of the orchestra situation. “The state had $1 million last year that went to the orchestra. That money was given back, and I thought that money could have gone to the musicians for their concerts.”

Kahn said that she would support public money going toward a contract settlement and that the city of Minneapolis and Hennepin County also should be involved.

“What they’ve done for sports teams, it’s not unreasonable to ask that they do something here,” she said.

John Stiles, a spokesman for Minneapolis Mayor R.T. Rybak, said no one has raised the issue of using city funds for the orchestra.

“Were it possible, it would require council action, and I’m not aware that any council member has raised it, either,” Stiles said.

The state, over the past decade, has supported bonding requests from the orchestra, the Guthrie Theater, the Cowles Center, the Children’s Theatre Company, the Minnesota History Center and the Ordway Center, among others.

In addition, individuals and organizations compete for grants through the Arts Board and regional councils. A recent survey by the National Assembly of State Arts Agencies ranked Minnesota first — by far — in the amount of money it spends per capita on the arts.