Two Republican lawmakers urged federal authorities and Fulton County's prosecutor to investigate whether Lt. Gov. Casey Cagle engaged in a "pay-to-play" scheme when he admitted to pushing legislation he didn't support to influence a super PAC.

The letter by state Sen. Bill Heath and state Rep. Susan Holmes, both supporters of Secretary of State Brian Kemp, asked prosecutors to launch an investigation into "compelling evidence of a direct quid pro quo offered by Cagle to trade legislative action for campaign funding."

It was addressed to U.S. Attorney B.J. Pak, FBI Special Agent Murang Pak and Fulton County District Attorney Paul Howard. And it cited two recent reports by The Atlanta Journal-Constitution and Channel 2 Action News involving the GOP candidate for governor.

The first was a secret recording from former rival Clay Tippins, who taped Cagle saying he supported "bad public policy" to expand a private school tax credit to prevent another opponent from getting support from the Walton Family Foundation.

The second involved Tippins' uncle, a GOP state senator and one-time Cagle ally, who said the lieutenant governor told him he had to pass a bill to boost charter school funding so he could get $2 million in funding from the group.

The foundation’s political arm has said speculation about its involvement in the race is “unfounded.” And Cagle has said his remarks were a "political exchange" and labeled his talk of outside support purely "rumor and innuendo."

Cagle campaign manager Scott Binkley called the letter the product of “irrelevant cranks” manipulated by Kemp’s campaign.

“If you take their charge at face value, then they need to be arrested for sending out a purely political letter for the Kemp campaign on what appears to be official state letterhead,” said Binkley.

“Where’s the quid pro quo? Casey didn’t get any money from these groups mentioned,” he added. “Kemp should apologize to these people for embarrassing them in public.”

The prospect of a formal investigation this close to an election – he faces Kemp in a July 24 runoff - is highly unlikely, and some legal experts say there’s little basis for a probe. Kemp’s allies hope to drive a different message over the next six weeks.

In the letter, the two lawmakers say the “undeniable evidence command a thorough investigation” from law enforcement officials into whether Cagle solicited campaign funds from the foundation or affiliated groups.

And they urge prosecutors to probe whether Cagle “rigged” other measures to hurt political opponents or benefit himself.

“These questions need to be asked by law enforcement,” the two wrote, “because Cagle has demonstrated repeatedly, notably on the audio recording provided by Clay Tippins, that he will lie with a straight face to the media and voters.”

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