New evidence that Sen. John Ensign (R-Nev.) actively sought to help his one-time top aide secure lobbying clients — potentially violating the Senate’s one-year revolving door ban — emerged Wednesday as the New York Times published e-mail messages between the GOP Senator, his former aide and others.

According to the Times, the messages have also been provided to the Senate Ethics Committee and the FBI, both of which are investigating Ensign’s involvement in procuring lobbying work for his former aide Doug Hampton after Ensign ended an affair with Hampton’s wife, Cynthia Hampton. A $96,000 payment Ensign’s parents made to the Hamptons is also under review.

The e-mails are the first indication that Ensign tried to help Hampton procure work at P2SA Equity, an energy investment firm. Media reports last fall indicated Ensign coordinated Hampton’s move to the firm November Inc. and helped him secure clients including Allegiant Air and NV Energy.

In an undated e-mail to Ensign, Hampton expresses concerns about his financial situation and references apparent promises from Ensign to help him find work.

“Regardless of the circumstance you ensured [sic] me that I would not be injured as a result of leaving your organization,” Doug Hampton wrote in the e-mail, portions of which were redacted. “Your best efforts to secure clients as [sic] not created a scenario whereby I was able to leave your organization which was in your best interest and not be impacted financially. ”

Ensign acknowledged having an affair with Cynthia Hampton, a former campaign aide for the Senator, last June. Since then, Doug Hampton, once a close friend to Ensign, has used numerous media appearances to detail the relationship and accuse Ensign of wrongdoing. Ensign had been viewed as a rising GOP star; he is up for re-election in 2012, and despite the scandal has insisted he will not resign his seat.

According to the Times, which also interviewed P2SA officials, Ensign suggested the firm hire Doug Hampton at a May 2008 meeting. The firm was seeking support for a Las Vegas biodiesel facility as well as a land swap with the Bureau of Land Management.

“We are excited about the assistance that you and your staff may be able to give us in regards to the Biodiesel and our properties south of Sloan,” P2SA official Bob Andrews wrote in on the of the e-mails. “Give me the information regarding next week’s fund-raising and we will certainly attend. Thanks again.”

The energy firm ultimately did not hire Hampton, however, the Times reported.

Ensign denied any wrongdoing in a statement to the Times.

“Senator Ensign has stated clearly, he has not violated any law or Senate ethics rule,” Ensign spokeswoman Rebecca Fisher told the Times. “If Doug Hampton violated federal law or rules, Senator Ensign did not advise him to do so, did not suggest that he do so, and did not cooperate with his doing so.”

Neither the Senate Ethics Committee nor the FBI commented to the Times on the report.