Could John Ensign face a Senate probe into the events surrounding his affair with a former staffer?

The government watchdog Citizens for Responsibility and Ethics in Washington has said it will file a complaint about the philandering Nevada lawmaker with the Senate Ethics committee, centering on whether either Cynthia Hampton or her husband Doug lost their jobs with Ensign because of the affair. Doug Hampton wrote in a letter to Fox News that the affair "led to our dismissal in April of 2008."

CREW's executive director, Melanie Sloan, told (sub. req.) Roll Call: "If the Hamptons, either one of them, were fired because the affair ended -- and Doug Hampton has alleged that, that they were dismissed because of the affair -- they should investigate."

And Sloan told the AP that such a dismissal would have violated a Senate rule against employment discrimination.

An aide for the committee wouldn't comment to the AP on whether it was already conducting a probe of the Ensign matter.