The fate of a ballot measure that would require secret ballots to form unions may hinge on whether voters think unions or employers are bigger bullies to workers.

The majority of spending that can be directly attributed to the landmark legal ruling that allows corporations, unions and other groups to spend freely on candidate campaigns largely affected Republicans in the Arizona primary election.

Proposition 113 is a battle of powerful interests, pitting the business community against labor unions. But so far, only the supporters are spending any money.

The Senate race in Legislative District 6, one of the Valley’s most conservative enclaves, best illustrates the ideological wrangling within the Republican Party.