Former senator Pete Domenici admits that he had a child out of wedlock. (J. Scott Applewhite/AP)

Former senator Pete Domenici of New Mexico, a Republican, disclosed Wednesday that he has a son born in secrecy over 30 years ago.

"More than 30 years ago, I fathered a child outside my marriage," Domenici told the Albuquerque Journal in a statement. "I deeply regret this and am very sorry for my behavior. I hope New Mexicans will view that my accomplishments for my beloved state outweigh my personal transgression."

Domenici said he kept the matter secret because the mother of the child, Michelle Laxalt, asked him to do so. Her father, Paul Laxalt, was himself a U.S. senator from Nevada from 1974 to 1987 and served as chairman of the Republican National Committee. He is still active in politics; the 90-year-old worked behind the scenes to build support in Nevada for Republican presidential candidate Mitt Romney. Laxalt declined to comment.

In her own statement to the paper, Michelle Laxalt said she asked Domenici to "agree that this remain private between the two of us." She raised the son, Adam Paul Laxalt, as a single mother. According to past Virginia voter registration records, he was born in August 1978, 35 years ago. Michelle Laxalt would have been 24 at the time; Domenici would have been 46.

"Given the fact that both my father and the father of my child were United States senators, I felt strongly that I would make this choice according to my values and would not seek advice, input or permission," she said. Laxalt's sister Kathleen (Neena) Laxalt was clueless.

Adam Laxalt is not commenting on his parents' relationship.

"I have lived my entire life as a private citizen and intend to remain one," he said. "I plan to address personal issues privately and will not be commenting or joining any public discussion."

The 80-year-old Domenici retired in 2008 after six terms, citing a degenerative brain disease. He and his wife, Nancy, have eight children. He told the Albuquerque Journal that his family has known about his affair for several months.

“I have apologized as best as I can to my wife, and we have worked together to strengthen our relationship,” he said.

Adam Laxalt is a lawyer working in Las Vegas, who served five years in the Navy. After a troubled adolescence that included a battle with alcoholism, he got a bachelors and law degree from Georgetown University. He provided legal counsel on detainee operations in Iraq. He also served as a law clerk for the U.S. Air Force general counsel; as an aide to John Bolton in the State Department; and as a staffer for former senator John Warner (R-Va.). He has written op-eds on health-care reform and Don't Ask Don't Tell, among other issues. Michelle Laxalt is the founder of a Washington lobbying firm who served in the Reagan administration.

Domenici is not the only lawmaker (or former lawmaker) to have hidden a child. Rep. Steve Cohen (D-Tenn.), who is unmarried, recently disclosed that he has a 24-year-old daughter whom he learned about three years ago. A 2008 drunken driving incident led former congressman Vito Fossella (R-N.Y.) to acknowledge his long-running affair and out-of-wedlock daughter. Essie Mae Washington-Williams, the mixed-race daughter whom Strom Thurmond kept secret for 70 years, died earlier this month. She revealed her parentage only after her father, a former senator from South Carolina, died in 2003.