National Geographic

Last month beleaguered GOP Sen. John Ensign announced that he wouldn't seek reelection in 2012. But today his aides revealed that Ensign will resign tomorrow.

Ensign has fallen under investigation by the ethics committee in the wake of an alleged sexual relationship with an aide and accusations that he steered business to her lobbyist husband. His departure could clear the way for Nevada's Republican governor to appoint Rep. Dean Heller (R) to the seat, giving the GOP an incumbent in 2012.

Scandal-plagued adulterer and defender of marriage Sen. John Ensign (R-NV) announced today that he will not seek reelection in 2012.

Nevada Sen. John Ensign, facing an ethics investigation stemming from an affair with a campaign aide, said Monday he would not seek reelection because he wanted to spare his family from an "exceptionally ugly" campaign. "At this point in my life, I have to put my family first," Ensign told reporters at a news conference in Las Vegas. Just two months into the 112th Congress, Ensign is the eighth Senate incumbent to opt out of running for a new term, out of 33 seats up in 2012. The announcement is welcome news to national Republicans who have admitted the two-term Republican would be vulnerable in the race. GOP Rep. Dean Heller, who won three statewide elections as secretary of State, is considered the party's best candidate to retain the seat.