(CNN) - One of the questions to emerge from that secret recording of a Mitch McConnell campaign strategy session is whether it proves the Senate Minority Leader is caught on tape misusing his congressional staff.
The DC-based watchdog group, Citizens for Responsibility and Ethics and Washington has asked the FBI to investigate.
CREW officials said the audio recording obtained by Mother Jones magazine raises questions "whether Sen. Mitch McConnell (R-KY), violated federal law and Senate rules by misusing Senate staff or resources to conduct opposition research on potential campaign opponents."
In the Mother Jones transcript, a campaign strategist at the McConnell meeting in February is quoted as thanking "LAs" or legislative assistants (legislative assistant being a title for a specific congressional staff position) for their work in developing opposition research on potential opponents, including actress Ashley Judd, who has since decided against a run for the Kentucky seat.
"So I'll just preface my comments that this reflects the work of a lot of folks: Josh, Jesse, Phil Maxson, a lot of LAs, thank them three times, so this is a compilation of work, all the way through," the unidentified strategist is quoted as saying in the liberal magazine's transcript.
But listen closely, and it's also possible that same adviser may have said "thank them for their free time." It's a bit garbled and all in the ear of the beholder. Listen for yourself here.
Congressional staffers are permitted to volunteer their personal time to political activities.
"This is a frivolous complaint based entirely on a maliciously transcribed, illegal recording and Melanie Sloan and CREW should be embarrassed for wasting the time of the Ethics Committee and the FBI," Brad Dayspring, a spokesman for the National Republican Senatorial Committee, wrote in a statement. "More importantly, Melanie Sloan should explain CREW's participation in a December meeting amongst Liberal groups where Mother Jones has reported that those present discussed "trying to oust Senate Minority Leader Mitch McConnell."
In the meantime, a source close the McConnell campaign confirms to CNN the FBI has pulled surveillance tape from the Kentucky building where the Minority Leader's campaign headquarters is located.
The source said the FBI's work suggests agents are looking into an "external source" for the audio's recording, not a leak from the McConnell campaign.
McConnell told reporters Tuesday he suspects a liberal Kentucky group is responsible for what he called a "Nixonian" operation.
"They apparently bugged my headquarters," he said Tuesday.
An actual bugging of a political campaign is so rare the allegation from the top Republican in the Senate immediately raised eyebrows across Washington.
Retired FBI agent Tom Fuentes, a CNN contributor, said the accusation warrants an investigation even if it sounds, as he called it, "pretty-far fetched."
"To actually do it, most serious campaign operators understand the ramifications," Fuentes said.