Ms. Cheney vowed to use her post on the House committee investigating Jan. 6 to continue prosecuting the public case against former President Donald J. Trump.
The nearly two-and-a-half-minute ad appeared aimed as much at a national audience as at voters in Wyoming, where she is badly trailing her primary opponent.
Representative Scott Perry’s lawyer said he was told he is not a target of the Justice Department’s expanding inquiry into one element of the effort to keep Donald J. Trump in power after his loss in 2020.