IOWA CITY, Iowa — An Iowa state senator resigned Wednesday after a special investigator found it likely he violated ethics rules by taking money from political entities connected to former presidential candidate Michele Bachmann and then denying he’d done so.

Sen. Kent Sorenson said that he had already decided he would not run for re-election, and that his resignation was best for his family. He said his decision was “absolutely not” an admission of wrongdoing.

“I’ve spent money fighting this that I shouldn’t have. I’m just not going to do that to my family anymore,” he said in a telephone interview.

His resignation came after attorney Mark Weinhardt said in a report released earlier in the day that it was “manifestly clear” Sorenson negotiated payments in 2011 that eventually reached $7,500 monthly in exchange for his work as Bachmann’s Iowa campaign chair. The money flowed from Bachmann’s political action committee, MichelePAC, and her presidential campaign to a Colorado consulting firm, which in turn paid Sorenson’s Iowa-based firm, Weinhardt wrote in the report filed with the Iowa Senate.

Sorenson’s compensation from MichelePAC is a violation of a Senate rule that bars senators from being paid by political action committees, Weinhardt wrote. Senators will have to decide whether the payments from her presidential campaign also violate the rule since it is unclear, he wrote.

Sorenson knew that accepting the compensation was improper, and later made false statements when he denied that he had taken money tied to Bachmann entities, Weinhardt wrote. Those statements might amount to misconduct in office, a felony that would also be a violation of the ethics rules, the investigator added.

Weinhardt was appointed to investigate an ethics complaint filed against Sorenson by a former Bachmann aide. Weinhardt’s report went to the Senate Ethics Committee, which is expected to meet to consider the report and what to do about it.

Before announcing his resignation, Sorenson said he disagreed with the report’s conclusions that he made false statements or that he had accepted compensation from Bachmann’s camp.

“I was never employed by Michele Bachmann. I was never employed by Bachmann for President. I was never employed by the PAC,” he said. “I had a corporation that worked for a corporation that worked for Michele Bachmann.”

Washington-based lawyer William McGinley, who’s representing Bachmann’s campaign, did not immediately return phone and email messages left by the AP.

The report contains the most detailed findings yet in a scandal that has swirled around Sorensen since he defected from the Bachmann campaign days before the 2012 Iowa caucuses to support Ron Paul. Bachmann, a Minnesota congresswoman, alleged then that Sorenson was switching allegiances due to payments from Paul’s campaign.

Weinhardt’s report said that Sorenson had received a $25,000 check from a Paul backer that Sorenson did not cash. Sorenson also received $73,000 in “deeply suspicious” wire transfers, but Weinhardt said he was unable to connect them directly to Paul’s campaign. Sorenson declined comment on the wire transfers Wednesday.

Peter Waldron, the former Bachmann aide who filed the complaint against Sorenson, said the case cried out for stronger ethics rules barring direct and indirect payments to state lawmakers from presidential candidates.

“I am pleased to be vindicated but naturally regret that the Iowa first-in-the-nation caucus position has been soiled by the events uncovered by the Special Counsel,” Waldron said in a statement.