Like a wind-whipped brush fire, the mass union protests that began in Madison, Wis., last week have spread to the capitals of Ohio and Indiana where Republican lawmakers also are trying to cripple the bargaining power of unions  and ultimately realize a cherished partisan dream of eradicating them. In each case, Republican talk of balancing budgets is cover for the real purpose of gutting the political force of middle-class state workers, who are steady supporters of Democrats and pose a threat to a growing conservative agenda.

In Ohio, Republican legislators, backed by Gov. John Kasich, have introduced a bill to end collective bargaining for state employees, in addition to imposing budgetary givebacks. Former Gov. Ted Strickland, a Democrat who was defeated by Mr. Kasich last year, has called the bill a “coordinated attack on the working middle class.” Thousands of union supporters showed up at the Capitol in Columbus on Tuesday, but the party appears to have the votes to pass the measure.

Across the border, Republicans are pushing a bill that would make Indiana what is misleadingly known as a “right-to-work” state. That means workers cannot be required to join public- or private-sector unions or pay dues, starving unions of the money they need to operate. Democrats in the Indiana House left the state to prevent a vote, tying up all legislation for two days. Thousands of workers have rallied on the Statehouse grounds. Gov. Mitch Daniels (who ended collective-bargaining rights for state workers in 2005) has supported the bill’s concept but on Tuesday urged Republicans to drop it because it could interfere with other items on his agenda.

Conservative leaders in most states with strong unions have in the past generally made accommodations with organized labor, often winning support on social issues in return. That changed this year after wealthy conservatives poured tens of millions of dollars into the election campaigns of hard-right candidates like Mr. Kasich and Gov. Scott Walker of Wisconsin.