Wisconsin? Maybe. Indiana? Sure. But could state legislators even be taking a shot at unions in super-liberal Massachusetts? On Wednesday, the state house overwhelmingly passed a bill that would bar public-sector employees from bargaining over health care—and in a twist, it’s Democrats leading the charge. They say it’s essential to saving the state money, but labor isn’t buying it. “It’s pretty stunning,’’ the president of the Massachusetts AFL-CIO said. “These are the same Democrats that all these labor unions elected.” But the bill may have a hard time passing the state senate, and it’s unclear whether Gov. Deval Patrick, also a Democrat, would sign the bill if it made it to his desk.