Many so-called reform ideas in education have appeared to have unstoppable momentum. Expanding merit pay and the increased use of standardized testing in teacher evaluation have enjoyed the backing of everyone from President Obama to former Florida Gov. Jeb Bush.

But now these ideas are experiencing pushback in the states, including some surprising places.

Teachers unions had already succeeded in 2011 in beating back an Ohio law that would have blocked collective bargaining rights. In part to ensure such action wouldn’t be taken again, the National Education Association put $1.4 million into a super PAC aimed at unseating GOP legislators in the state last fall. One of their favored weapons was teachers themselves. A dozen teachers ran for state legislative seats in Ohio. They didn’t do too well: Only one of them won (joining two other teachers in the state Legislature).

But teachers unions enjoyed big success last fall in beating back states’ policies they don’t like, unseating Indiana state Superintendent Tony Bennett, a champion of the reform approach, and overturning multiple laws regarding matters such as tenure that had been enacted in Idaho and South Dakota. “People responded to the notion that it doesn’t make sense in trying to improve education to limit the voices of teachers, which was at the heart of this union-busting legislation,” says Brian Cronin, a former teacher and legislator in Idaho.

The results bode ill for some fashionable policy ideas that had appeared to enjoy bipartisan support, says Rick Hess, director of education policy studies at the American Enterprise Institute. “Some of the reform agenda doesn’t connect with a lot of middle-class, suburban voters,” Hess says. He notes that not only unions but also many Tea Party conservatives opposed some of the policy ideas. He argues this puts at risk the Common Core standards that have been widely embraced by states.

Certainly, centrists in both parties will be left “on a tightrope,” says Andrew Rotherham, an education consultant and columnist. “On all these state issues, unions flexed their muscles,” he says. “In the places where they decided to go and have a fight on this stuff, they did pretty well.”