Updated

Senator Mitch McConnell’s campaign manager resigned Friday in the wake of a scandal involving former Texas Rep. Ron Paul’s 2012 presidential campaign, where he had been a top aide.

Jesse Benton said the decision to leave the staff of McConnell, R-Ky., “breaks my heart” but “inaccurate press accounts and unsubstantiated media rumors about me and my role in past campaigns” were becoming a distraction in McConnell’s efforts to win re-election in November.

His announcement stems from a political scandal in Iowa. Earlier this week, a former Iowa lawmaker pleaded guilty to federal charges stemming from his switch of support from one Republican presidential candidate to another before the 2012 Iowa caucuses.

Former state Sen. Kent Sorenson received thousands of dollars in "under the table payments" before switching loyalties from Michele Bachmann, whose Iowa campaign he headed, to Paul, then lied to federal investigators about the money, the Justice Department said. Prosecutors refused to say which campaign paid Sorenson.

Benton, a Tea Party insider, worked as a top aide to Paul.

In a separate statement Friday, McConnell's campaign said the senator "obviously has nothing to do with the Iowa presidential caucus or this investigation, so it would be inappropriate for his campaign to comment on this situation."

Benton was mentioned in documents gathered during an Iowa state ethics probe of Sorenson, a complaint to the Federal Election Commission and e-mails purported to be from the Ron Paul campaign obtained by the non-partisan Center for Responsive Politics, which monitors federal campaign finance issues, The Courier-Journal of Louisville reported.

McConnell, the Senate minority leader, is in a tight race for a sixth term against Democrat Alison Lundergan Grimes, Kentucky’s secretary of state.

Charly Norton, a spokeswoman for the Grimes campaign, said in a statement, "Sen. McConnell owes the people of Kentucky a full account of what he knew and when he knew it."

In his resignation statement, Benton said, “recently, there have been inaccurate press accounts and unsubstantiated media rumors about me and my role in past campaigns that are politically motivated, unfair and, most importantly, untrue... the press accounts and rumors are particularly hurtful because they are false.

“However, what is most troubling to me is that they risk unfairly undermining and becoming a distraction to this reelection campaign.”

He said his resignation would take effect Saturday.

The Associated Press contributed to this story