McConnell has asked the FBI to investigate how a campaign strategy session regarding a possible challenge by Ashley Judd was recorded and delivered to Mother Jones, the same publication that released the infamous video of Mitt Romney's "47 percent" speech.
The Hill reported McConnell, R-Ky., accused the Kentucky Democratic super-PAC Progress Kentucky of planting a bug and recording a strategy session involving McConnell and his aides in which they discussed using Judd's religious beliefs and history of depression as part of an attack strategy.
Judd, a longtime liberal activist and actress, had been considering challenging McConnell for his seat in 2014 but has since decided against a run.
"Senator McConnell's campaign is working with the FBI and has notified the local U.S. attorney in Louisville, per FBI request, about these recordings," McConnell campaign manager Jesse Benton said in a statement.
"Obviously a recording device of some kind was placed in Senator McConnell's campaign office without consent. By whom and how that was accomplished presumably will be the subject of a criminal investigation."
The Hill said Progress Kentucky has yet to respond to the charges.
The audio tape has McConnell and members of his staff discussing how they would attack Judd on the campaign trail if she did run.
At one point, they evaluate the portions of Judd's autobiography where she discusses her history of depression.
"She's clearly, this sounds extreme, but she is emotionally unbalanced," a male voice can be heard telling the group. "I mean it's been documented. ... She's suffered some suicidal tendencies. She was hospitalized for 42 days when she had a mental breakdown in the '90s."
At another point the group mocks an audio clip played of Judd describing her belief in God as rooted in nature, invoking St. Francis of Assisi and "Brother Donkey, Sister Bird." One unidentified aide predicts conservative Christians would "take to the streets with pitchforks" after hearing Judd's views on religion.