A campaign finance watchdog has filed a complaint against former GOP presidential candidate Rick Santorum, referring to reports that Santorum or his campaign may have illegally urged a donor to donate $1 million to a super PAC supporting Santorum.

The donor, energy executive William Dore, in a recent interview said he approached Santorum about giving his campaign $1 million. He initially said Santorum urged him to instead give the money to the super PAC, Red White and Blue Fund, which can accept unlimited donations. Santorum’s campaign is subject to much lower contribution limits and could not accept such a donation.

Dore later recanted, saying it was Santorum’s staff who directed him to give to the super PAC.