Fifty years after the military dictatorship, Argentina’s government is defunding human rights groups and promoting a revisionist account of the junta’s crimes.

Gov. Kevin Stitt selected Mr. Armstrong, a fellow Republican and an energy executive, to play a caretaker role in the seat until the next election.

A Kansas law required a passport, a birth certificate or other proof of citizenship to register, but it was struck down after a court found that around 31,000 eligible voters had been blocked.