A Justice Department spokesman said Thursday that Mr. Gonzales did not remember the discussions cited in the e-mail. “The attorney general has no recollection of any plan or discussion to replace U.S. attorneys while he was still White House counsel,” said Tasia Scolinos, the department spokeswoman.

“The period of time referred to in the e-mail was during the weeks he was preparing for his confirmation hearing, Jan. 6, 2005, and his focus was on that,” Ms. Scolinos said. “Discussions of changes in presidential appointees would have been appropriate and normal White House exchanges in the days and months after the election as the White House was considering different personnel changes administrationwide.”

When the Rove inquiry described in the Jan. 6 e-mail message — sent by Colin Newman, a White House lawyer, to David G. Leitch, another lawyer — was forwarded to Mr. Sampson, then a top aide in the Justice Department, he replied with an outline of his thinking, as presented to Mr. Gonzales. “As an operational matter we would like to replace 15-20 percent of the current U.S. attorneys — underperforming ones,” Mr. Sampson wrote.

In the message, Mr. Sampson said, “The vast majority of U.S. Attorneys, 80-85 percent, I would guess, are doing a great job, are loyal Bushies, etc.”

Even then, Mr. Sampson realized there might be a backlash caused by replacing a large number of prosecutors and said it would be “weird” to remove prosecutors before they had completed a single four-year term. “I suspect that when push comes to shove,” he wrote, “home state senator likely would resist wholesale (or even piecemeal) replacement of U.S. Attorney they recommended.”

The White House and Justice Department have defended the dismissals as appropriate, pointing out that the prosecutors are political appointees who serve at the pleasure of the president. But some of the fired prosecutors told Congress that Republican lawmakers had pressed them about corruption or voter fraud investigations, provoking charges from Democrats that the dismissals may have been political and that they threatened the traditional independence of the prosecutors.

The White House has said Mr. Rove passed on complaints to the White House counsel’s office, and perhaps to Mr. Bush, about prosecutors’ failure to investigate voter fraud cases. He also pushed for the appointment of a former aide as the United States attorney in Arkansas, which outraged local officials and the state’s senators because the prosecutor, J. Timothy Griffin, had limited experience.