Arizona Public Service's apparent "dark money" spending for two Arizona Corporation Commission members appears to have paid off.

Four Republican candidates were vying for two open seats on the commission in Tuesday's primary election, and the two who APS allegedly preferred were comfortably in the lead.

See also: -Home Solar Takes Hit After Vote by Corporation Commission to Add Surcharge

Doug Little, a gun range operator and former software executive, and Tom Forese, an education-software executive, were the benefactors of millions in campaign spending by groups including the Free Enterprise Club. The independent groups didn't have to divulge the source of their funding, leading to speculation that APS had donated the money. APS, when asked by reporters about that possibility, would not confirm or deny it had made the donations.

With 36 percent of voting precincts reporting at 11 p.m., Little and Forese each had 29 percent of the vote.

Their next closest competitor, State Representative Lucy Mason, trailed well behind with 23 percent. Former Paradise Valley Mayor Vernon Parker, meanwhile, came in last in the GOP primary race with 18 percent. Reached by phone on Tuesday night, Parker sounded bitter.

The targeting of specific GOP candidates in the Corporation Commission race, plus spending against State Treasurer candidate Hugh Hallman [who opposed APS' plan to charge rooftop solar customers more for the electricity they generate] is a "horrific precedent," he said.

"This is not good, when a regulated monopoly can choose who regulates them," Parker said, adding that the election could result in higher utility rates for Arizonans. "For me to have to overcome millions of dollars and negative ads -- it's an abomination of the political process."

The two GOP winners, if elected, would be "hard-pressed not to do what APS wants," Parker said.

Arizona Congressman David Schweikert, who was at the Republican Party's primary party at the Hyatt Regency on Tuesday, said the possibility that APS spent dark money to support specific Corporation Commission candidates "really concerns me on multiple levels."

Schweikert wondered whether any "upside" existed for APS or the two winning GOP candidates, who -- if elected -- would remain under a "shadow of a perception of conflict of interest."

During the race, Forese and Little typically didn't comment to reporters about the spending, which by law should not have been coordinated with the candidates.

The two GOP winners will go on to face Democrats Jim Holway and Sandra Kennedy in the November 4 general election.

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