Duffy would probably do better than Trump in the WOW counties but worse in the traditionally Democratic rural counties, unless Trump is really popular.
How? He represents WI-07, the most Trumpy district in the state, and was an early backer of Trump, who never backed down. I think Duffy is the perfect statewide candidate for Wisconsin: He does great in his home district, should do similar to Johnson in the similar WI-03 and -08, while doing well in WOW (pretty evangelical, won't like atheist lesbian progressives). He is also very well-known nationally. I see him on The Situation Room A LOT (his wife also frequently appears on TV). Funny but also very well spoken, and one of my favorite Congressmen. Republicans' ideal candidate.