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Democrats in the Senate are asking for an investigation into whether FCC Commissioner Michael O'Rielly violated federal law by endorsing President Donald Trump at last month's Conservative Political Action Conference, according to CNN.

The letter, signed by seven Senate Democrats, was sent to the Office of Special Counsel and the FCC inspector general on Tuesday. Specifically, the senators say O'Rielly's response to a question about "regulatory ping-pong" around issues like net neutrality is a violation of the federal Hatch Act, which prohibits federal employees from engaging in politics while on the job.

"I think what we can do is make sure as conservatives that we elect good people to both the House, Senate and make sure that President Trump gets re-elected," O'Rielly said, according to the letter, which CNN said it obtained.

The senators say that O'Rielly was endorsing Trump in that statement. The letter argues that O'Rielly was appearing at CPAC in his official capacity as commissioner and that he was "promoting a political candidate who has already filed election paperwork."

Representatives from the FCC, the Office of Special Counsel and FCC inspector general's office did not immediately respond to a request for comment.

The letter was signed by Sens. Catherine Cortez Masto of Nevada, Tom Udall of New Mexico, Maggie Hassan of New Hampshire, Ron Wyden of Oregon, Mazie Hirono of Hawaii, Richard Blumenthal of Connecticut and Tina Smith of Minnesota.

Last week a government ethics watchdog group, the Project on Government Oversight, also asked for an investigation regarding O'Rielly's comments at CPAC.

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