Arizona voters last fall overwhelmingly approved Proposition 211 by a 3-1 margin.
Now a judge has rejected a bid by two groups attempting to void the effort to end "dark money" in political races.
It requires anyone that spends more than $50,000 on a statewide race to disclose the identities of those who contributed at least $5,000.
In his Thursday ruling, Maricopa County Superior Court Judge Scott McCoy rejected arguments from the Arizona Free Enterprise Club and Center for Arizona Policy.
They claimed that the disclosure requirements violate the rights of donors to affect candidate races and ballot measures.
McCoy wrote the framers of the state’s constitution established a commitment to pure elections, to prevent corporate influences and to publicize sources of campaign funds.
