Benton told the Herald-Leader that he met with McConnell on Friday afternoon and offered his resignation, which McConnell "reluctantly accepted."
Benton said he offered his resignation, effective Saturday, with a "heavy heart."
He maintained his innocence, faulting "inaccurate press accounts and unsubstantiated media rumors."
"This decision breaks my heart, but I know it is the right thing for Mitch, for Kentucky and for the country," Benton said.
Benton's name has surfaced in connection to a bribery scandal dating to his time as former U.S. Rep. Ron Paul's political director during the 2012 presidential election.