ALBUQUERQUE, NM — Former Sen. Pete Domenici has disclosed that he fathered a secret child in the 1970s with the 24-year-old daughter of one of his Senate colleagues — a startling revelation for a politician with a reputation as an upstanding family man.Domenici and Michelle Laxalt sent statements to the Albuquerque Journal that announced the relationship for the first time and identified their son as Nevada attorney Adam Paul Laxalt. They said they decided to go public with their decades-old secret because they believed someone was about to release the information in an attempt to smear Domenici.“I deeply regret this and am very sorry for my behavior,” Domenici, 80, said in his statement. “I hope New Mexicans will view that my accomplishments for my beloved state outweigh my personal transgression.”The Journal reported on the relationship in an article published Wednesday.Domenici was the longest-serving senator in New Mexico history when he retired in 2008 after six terms. He was known for his unflagging support of the state’s national laboratories and military installations, and he became a power broker for his work on the federal budget and energy policy. Domenici voted for the impeachment of former President Bill Clinton in 1998 after his affair with Monica Lewinsky, but his floor statement focused on the fact that Clinton had lied under oath, noting that the trial “has never been about the President’s private sex acts, as tawdry as they have been.”But in the same speech, he cited the value of “truthfulness” and how it’s the first pillar of good character. Reached at his home in Washington on Wednesday, Domenici said he had nothing more to say. Domenici and his wife have been married more than 50 years and have eight children.The scandal has all the elements of an inside-the-Beltway soap opera.Michelle Laxalt is the daughter of former U.S. Sen. Paul Laxalt, himself a significant political figure in the 1970s and ’80s as he served as Nevada governor and two terms in the Senate alongside Domenici.Michelle Laxalt became a prominent lobbyist, Republican activist and television commentator after the affair. She said in the statement that she chose to raise her son as a single parent and that the two agreed that it would be a private matter.“One night’s mistake led to pregnancy more than 30 years ago,” she said.Laxalt’s prominence in national politics occasionally put her in an odd position of publicly discussing the integrity of the man who is the father of her child. In 2008, Domenici was reprimanded by the Senate ethics committee for his involvement in a scandal over the Bush administration’s firing of eight U.S. attorneys. At the time, Laxalt defended Domenici’s integrity on CNN, calling him an honorable man who was supporting “no fewer than eight children.” The website for Adam Laxalt’s law firm said he is a former U.S. Navy officer and lawyer who served in Iraq. He also worked for then-Sen. John Warner, R-Va., and as a special assistant to an undersecretary of state, according to the website. He has also written a number of conservative columns against policies like Obamacare and the lifting of the military’s “don’t ask, don’t tell” policy for gays for publications like the National Review Online, American Spectator and the Las Vegas Review-Journal. And he serves on the board of Catholic Charities of Southern Nevada.Domenici said he was sorry that he caused hurt and disappointment for his wife and other family members. He said he disclosed the situation to his family several months ago.“I have apologized as best as I can to my wife, and we have worked together to strengthen our relationship,” Domenici said.Domenici told the Journal his son participated in the drafting of his statement, but it was unclear if the two had a prior relationship.The Laxalts did not immediately respond to emails and phone calls seeking comment.