WASHINGTON – Republican John Ensign of Nevada apologized Monday to an all but empty Senate chamber for his extramarital affair with a former aide and hoped his legislative record would speak for him.

Ensign announced in June 2009 that he had an extramarital affair with Cynthia Hampton, a former member of his campaign staff. Amid the scandal, his parents provided Hampton with $96,000, described as a gift, and Ensign helped find Doug Hampton, the aide’s husband, a lobbying job. He announced his resignation in late April.

Ensign’s farewell speech was notable as much for who was not there as for what he said. Not a single colleague came to hear him speak or to pay tribute to his service. The gallery was empty of family members and staffers who often pack its seats for such occasions. Five of Ensign’s staffers lined a bench on the Senate floor during his address; one could be seen wiping a tear.

In the presiding officer’s chair, freshman Sen. Chris Coons, D-Del., opened a folder on his desk and appeared to begin writing remarks on a separate matter when Ensign began speaking.

“I was blind to how arrogant and self-centered that I had become,” Ensign said. “The urge to believe in it was stronger than the power to fight it.”

Before the affair became public, Ensign had been highly critical of colleagues who had fallen from grace.

Ensign said he regretted judging two scandalized colleagues, former Sen. Larry Craig, R-Idaho, and the late Ted Stevens, R-Alaska, and calling for their resignation. Later, Ensign privately apologized to them.

Nevada Gov. Brian Sandoval has appointed Rep. Dean Heller to complete Ensign’s second term. The general election for that seat will take place in November 2012.