The Chicago Teachers Union has voted overwhelmingly to strike. View Full Caption DNAinfo/Ted Cox

RIVER NORTH — Nearly 96 percent of Chicago Public Schools teachers who cast a vote last week agreed to authorize a strike, setting the stage for a walkout as soon as Oct. 11.

The union said 95.6 percent of Chicago Teachers Union members who voted last week opted to approve the first strike since 2012. Last week's voting process was criticized by some because teachers could see how one another voted.

The union's House of Delegates meets Wednesday and could set a strike date for as soon as Oct. 11. The union has to give 10 days' notice before a walkout.

At very least, the strike vote is expected to spur ongoing negotiations on a new contract.

"A strike can be averted, and CPS will work tirelessly to make sure children’s education and progress is not interrupted," said district spokeswoman Emily Bittner. “A strike is a very serious step that affects the lives of thousands of parents and children, and we hope that, before taking the final steps toward a strike, the CTU’s leadership works hard at the bargaining table to reach a fair deal."

According to the union's Rules & Election Committee, there was a 90.6 percent turnout of its members, leading to the overwhelming vote to strike. With 95.6 percent of voters backing a strike, that easily surpassed the 75 percent threshold necessary to OK a strike.

In that, the union rebuffed calls from Mayor Rahm Emanuel and CPS Chief Executive Officer Forrest Claypool to be "part of the solution" and stay on the job while negotiations continue.

Teachers have been working without a contract since the middle of last year. Union President Karen Lewis stated in a letter to teachers earlier this month that "we will not work another year without a contract."

Teachers have attempted to enlarge the debate by saying they're fighting to defend public education and have called for the city to find additional revenue rather than rely on cuts. They have also resisted a district proposal for them to pay a 7 percent pension contribution CPS has been responsible for since the '80s. The union insists that payment was hard-earned at the bargaining table, and paying it would amount to a 7 percent cut in pay. Lewis has said explicitly that "our members have been very clear" they reject that proposal, and she called it "strike-worthy" over a year ago.

Bittner insisted CPS was offering teachers a raise overall, adding that they "have helped propel Chicago students’ remarkable academic gains — so even in a difficult financial environment, CPS is offering teachers a raise that was already supported by both the CTU leadership and an independent third-party arbitrator."

Teachers approved a strike last December by the same 96 percent vote, and went on to reject a contract offer from CPS earlier this year — a deal Lewis then acknowledged as a "serious offer" — but they pulled the plug on a threatened late-spring strike, instead conducting a one-day walkout April 1.

CPS was cheered by the passage of a stopgap budget by the General Assembly over the summer, which also cleared the way for a $250 million increase in property taxes for the district. Yet strike talk reignited after CPS imposed new budget cuts as the school year approached.

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