Retired federal judge Michael Mukasey will be sworn in today as the nation’s 81st attorney general in a low-key ceremony at the Justice Department.

Mukasey was confirmed by the Senate late Thursday on a 53-40 vote. Six Democrats and 46 Republicans voted to confirm him. The vote was one of the narrowest ever for an attorney general nominee.Justice officials said Mukasey’s swearing-in today will allow him to handle official documents during the weekend and get briefings from senior Justice officials right away. A public swearing-in ceremony will not take place until next week.Key supporters, such as Sens. Charles Schumer, D-N.Y., and Dianne Feinstein, D-Calif., who had broken ranks with Democrats in the Senate Judiciary Committee two days earlier, said they voted for him because the alternatives to Mukasey were much worse, in that the president could fill the post with a recess appointment. They also said Mukasey reassured them that he would enforce any law Congress passed specifically addressing waterboarding, an interrogation technique that simulates drowning and that many regard as illegal.”This is the best chance we have,” Feinstein said during a four-hour debate over the nomination Thursday, which ended with the vote at about 11:30 p.m.Mukasey had been widely praised after his nomination by President George W. Bush on Sept. 17 as a respected jurist with vast legal experience.But Mukasey ran into trouble on his second day of confirmation hearings, when he refused to say whether waterboarding constitutes torture. The technique involves pouring water on the covered face of a bound detainee.In follow-up answers to written questions, Mukasey said he found the practice “repugnant” but was reluctant to equate it with torture because he had yet to be briefed on the classified program. He also said he didn’t want to divulge any information that may aid the enemy or let his “uninformed” opinion influence the work of government interrogators.Mukasey, 66, also was criticized throughout the confirmation hearings for his expansive views on presidential powers and the extent of executive privilege.Mukasey was a federal prosecutor and a white-collar attorney before President Ronald Reagan tapped him in 1987 to become a federal judge in New York’s busy Southern District. He became the chief judge in 2000 and retired last year to rejoin the New York firm of Patterson Belknap Webb & Tyler.