However, the FBI's newly released indictment might cast some doubt on that: It includes quotes from the former campaign manager suggesting he might have told Donovan about the deal.

When asked by the finance chairman if Donovan was "good with this," the campaign manager replied, "Yeah... I'm, you know, doing everything I can."

Donovan, the onetime front-runner for the open seat, is facing a tough challenge from attorney Elizabeth Esty (D) in the slightly Democratic-leaning district.

The Hill rates the race "lean Democratic," and, if Donovan wins the Aug. 14 primary, is likely to move the race into the "toss-up" category.