John Curtis, the mayor of Provo, Utah, won the Republican primary on Tuesday to fill the United States House seat vacated by Jason Chaffetz, a Republican who resigned from Congress on June 30.

Mr. Curtis will be the favorite against the Democrat Kathie Allen, who was nominated at her party’s June convention. But the general election in November does have a wrinkle that could complicate things for the Republicans: A federal judge ordered the newly created United Utah Party to be allowed on the ballot. The party, billing itself as a moderate alternative, has nominated Jim Bennett, the son of the former Utah Senator Robert F. Bennett, for the seat.

Results for tonight’s special election in Alabama »