Representative John Faso must think very little of his constituents in New York’s 19th Congressional District in the Hudson Valley and the Catskill Mountains.

He’s counting on them to be bigots.

How else can we explain Mr. Faso’s contention that his Democratic challenger, Antonio Delgado, is unfit for office because he had a career as a rapper a decade ago?

“Mr. Delgado’s lyrics are offensive, troubling and inconsistent with the views of the people of the 19th District and America,” Mr. Faso, a Republican, said in a statement last week.

Mr. Faso, who has heartily embraced President Trump’s agenda, is having a hard time. He is fighting to hold on to one of the most vulnerable Republican seats in the country, facing a rising swell of Democratic momentum in a district that voted for Barack Obama twice but went to Donald Trump in 2016. A recent poll, commissioned by the Democratic Congressional Campaign Committee this month, found Mr. Faso trailing Mr. Delgado by seven percentage points.