Rove was scheduled to speak Saturday on behalf of Jerry Kilgore, the Republican candidate for governor of Virginia, before an audience of 300 in Tysons Corner. Instead, the audience heard from Republican National Committee Chairman Ken Mehlman.
No detailed explanation was given, The Washington Post reported. The incident occurred one day after Rove made his fourth appearance before a federal grand jury investigating the disclosure of a CIA agent's identity.
Fitzgerald has interviewed dozens of Bush administration officials, and some familiar with the prosecutor's questions believe he is looking also at the possibility of obstruction of justice, perjury or conspiracy charges in the case.
Many of those attending the event Saturday shrugged off Rove's cancellation, said The Post -- including Kilgore.
"I was coming anyway, regardless," he said. "I like Ken Mehlman, too."