Michael Alfonso, the son-in-law of Transportation Secretary Sean Duffy, has clinched the Republican nomination for Wisconsin’s 7th Congressional District after securing a endorsement from President Trump. The 26-year-old candidate, who graduated from the University of Wisconsin-Madison with a mathematics degree and married Mr. Duffy’s daughter Evita Duffy at age 22, defeated Kevin Hermening—a former Marine detained during the 1979 U.S. embassy hostage crisis—in Tuesday’s primary contest.

Alfonso’s campaign highlighted his ties to the Duffy family, noting that he is the son-in-law of Transportation Secretary Sean Duffy and Rachel Campos-Duffy, a Fox News anchor. He described himself as a “young ‘STAR’” championing policies such as tax cuts, economic growth for farmers and ranchers, and border security. Alfonso cited the recent assassination of conservative activist Charlie Kirk—a key figure in mobilizing pro-Trump student groups—as his primary motivation for entering office.

Alfonso’s residency eligibility faced scrutiny after he registered to vote in Wisconsin shortly before Trump’s endorsement, listing an address tied to Mr. Duffy’s property. His campaign has emphasized his background working as a producer on Dan Bongino’s podcast and his commitment to helping young Wisconsinites afford homes and families.

Alfonso will face Democrat Fred Clark, a former state assemblyman who entered the race after winning Wisconsin’s 7th District Democratic primary with a focus on “real people” in northern communities. The seat has been held by Republican Rep. Tom Tiffany since 2020, following Transportation Secretary Duffy’s resignation due to his child’s health issues.