A trend that began after Arizona started letting independents vote in partisan primaries reached fruition this month when they officially became the largest voting bloc in the state, outnumbering registered Republicans by a few thousand.

Critics of the state’s new election law today filed papers to create a political committee that will challenge the legislation through a referendum.

Voters responded with a resounding ‘no’ on Proposition 121, also known as the “top two” primary system, which would have created one primary for all candidates.