Holder is asking a federal appeals court to send the cases of former Alaska state representatives Victor Kohring and Peter Kott, back to the trial judge, because prosecutors again failed to turn over key evidence to the defense.
Similar problems negated the conviction of former Sen. Ted Stevens, an Alaska Republican.
In announcing the move Thursday, the Justice Department said it is also asking the appeals court to release the two men on their own recognizance.
The department is not dropping the charges.
"After a careful review of these cases, I have determined that it appears that the department did not provide information that should have been disclosed to the defense," Holder said in a statement. "When we make mistakes, it is our duty to admit and correct those mistakes."
Kohring was convicted in November 2007 of bribery and extortion-related charges and sentenced in 2008 to 3½ years in prison. Kott was also convicted in 2007 and sentenced to six years in prison.
Thursday's actions grow out of a review prompted by the problems with the Stevens case.
When Stevens' conviction was tossed out in April, the attorney general ordered a more extensive review of possible prosecutorial missteps, particularly among the lawyers handling public corruption cases. A judge has separately ordered a second investigation into the conduct of many of the lawyers involved.
Messages left Thursday with attorneys for both Kott and Kohring were not immediately returned.