Senate candidate Todd Tiahrt is attacking Republican rival Jerry Moran over tax issues in a new television ad.

Moran’s campaign suggests Tiahrt is desperate and noted Wednesday that blank tax forms pictured in the new ad are from New York.

Tiahrt’s ad highlights six votes Moran made to raise taxes, most of them as a state legislator in the early 1990s. It also cites a 2003 vote on a budget resolution in the U.S. House.

Tiahrt is trying to persuade GOP voters ahead of the Aug. 3 primary that Moran isn’t a true conservative.