MARBLEHEAD – Ten-year Selectman Harry Christensen told his colleagues Wednesday evening that he expects to step down in May."It is unlikely that I will be a candidate this year," he said.Among the reasons for his decision are a "mushrooming" law practice, his work with the Historical Commission and his son Matthew and daughter-in-law Laura, who have three children under 4 years of age – one of them just born a week ago – and they will need grandparent support transitioning from Matthew’s Army service to civilian life.Christensen said he had an associate he had been trying to convince to run for selectman and it looked as if he would. He declined to say who it was. "He can make his own announcement," Christensen said."I will be back," he added. "This is not my swan song. I just need a couple of years."Characteristically, he thanked Town Administrator Tony Sasso for keeping him out of trouble, especially during his tenure as chairman.Christensen has practiced real estate law in Marblehead for the past 25 years. He is a decorated Vietnam War veteran who received the Silver Star and Purple Heart with Cluster.In addition to serving as chairman of the selectmen for two of his 10 years, he has also served as a corporator of the Marblehead Savings Bank, president and director of the Marblehead Rotary Club, a board member of the Marblehead Visiting Nurses Association, Community Counseling Center, Citizen’s Scholarship Foundation and Anchor to Windward and commander of Marblehead VFW Post #2005. He is a member of Philanthropic Lodge, Masons.Christensen ends each selectmen’s meeting by asking the audience to remember those who are serving their country. Wednesday night he asked his colleagues to remember the people fighting to survive in Haiti before announcing his decision."I ran for selectman 10 times and each time I was elected," he said. "I want to thank the people who voted for me. It’s been a privilege to serve."