Geographically, he cuts into Didier's base. No idea where he stands ideologically.
I was under the impression Didier was from Grant County (Ephrata). It seems Peck getting in hurts Sharon Brown more than him.
While we're on the subject of geography, it's worth noting most of Newbry Holmquist's district isn't in this CD (it's split between the 8th and the 5th). And if Didier is from Ephrata, all she really has is Moses Lake (population 21,000).
If I were a Republican officeholder from Yakima County, I'd get in this thing quick.