Attorney General Alberto Gonzales, fighting to save his job, said in prepared Senate testimony Sunday he has "nothing to hide" in the firings of eight federal prosecutors but claimed a hazy memory about his involvement in them. Two Republican senators said Gonzales has yet to shore up his credibility amid shifting explanations of his role in the dismissals. Vice President Dick Cheney reaffirmed White House support for the attorney general — but left it to Gonzales to defend himself to lawmakers who have called for his resignation.

In his 25-page statement, Gonzales apologized for embarrassing the eight U.S. attorneys and their families by letting their ousters erupt into a political firestorm that has engulfed the Justice Department since January. He maintained the firings were not improper, but said he remembers having only an indirect role in the plans beyond approving them.

"I have nothing to hide, and I am committed to assuring the Congress and the American public that nothing improper occurred here," Gonzales said in prepared testimony released before he appears Tuesday before the Senate Judiciary Committee. The panel, which oversees the Justice Department, is investigating whether the firings were politically motivated.

"I am sorry for my missteps that have helped to fuel the controversy," he said.

Gonzales added: "In hindsight, I would have handled this differently. ... Looking back, it is clear to me that I should have done more personally to ensure that the review process was more rigorous, and that each U.S. attorney was informed of this decision in a more personal and respectful way."