Three recall elections for Wisconsin Democratic state senators have been certified, starting the clock for Republicans to officially declare their candidacies.

Six Republican senators also face recall elections, all of which will be held in July and August in the largest concerted effort to remove incumbents from office during their terms in Wisconsin history.

The Government Accountability Board certified the recalls for the Democrats on Friday. Candidates wishing to run against them have until June 21 to file with the board. The deadline for candidates running against the six Republicans is Tuesday.

The senators were targeted for the positions they took on Republican Gov. Scott Walker's proposal taking away collective bargaining rights from most state workers. Republicans pushed through the law, but the state Supreme Court is weighing an appeal.