MADISON, Wis. (AP) - Wisconsin school districts are warning teachers that their contracts might not be renewed as Gov. Scott Walker's plan to cut nearly all public employees' collective bargaining rights remains in limbo.

The proposal took a concrete step forward Friday when Republicans in the state Assembly abruptly approved the bill and sent it to the Senate after three straight days of debate and amid confusion among Democrats. But with all 14 Democratic state senators still out of state, another stalemate awaits the measure that Walker insists will help solve budget deficits and avoid mass layoffs.

The legislative gridlock prompted the Wisconsin Association of Schools Boards to warn districts that they have until Monday to warn teachers of possible nonrenewal of contracts. That's because if Walker's bill becomes law, it would void current teacher collective bargaining agreements that lay out protocol and deadlines for conducting layoffs.

New London district administrator Bill Fitzpatrick said he had been authorized by his school board to issue nonrenewal notices to all 180 district teachers, but was negotiating a deadline extension with local teachers union officials to avoid sending the notices en masse.

"It's like going to the doctor and being told you might have some kind of disease but that's the only thing they can tell you," Fitzpatrick said Friday. "This fear of the unknown, of not knowing the future of your livelihood - that's what the people in this building are worried about right now."

Despite the uncertainty created by the absence of the Senate Democrats, who fled more than a week ago to block a vote on Walker's bill, Marshfield kindergarten teacher Jane Cooper said she blames Republicans.

"They are trying to bust our union," Cooper said. "That is huge."

The flashpoint in Walker's proposal is language that would require public workers to contribute more to their pensions and health insurance and strip them of their right to collectively bargain benefits and work conditions.

It contains a number of provisions he says are designed to fill the state's $137 million deficit and lay the groundwork for fixing a projected $3.6 billion shortfall in the upcoming 2011-13 budget.

Democrats and unions see the measure as an attack on workers' rights and an attempt to cripple union support for Democrats. Union leaders say they would make pension and health care concessions if they can keep their bargaining rights, but Walker has refused to compromise.