South Dakota's legislature referred Constitutional Amendment J to the November 3, 2026 ballot, adding explicit language disqualifying noncitizens from voting in state and local elections amid recent voter roll reviews that removed hundreds of noncitizens and new state requirements for citizenship documentation. Republican lawmakers frame the measure as closing a constitutional gap to protect election integrity, while Democratic opponents highlight risks of challenges to eligible voters' registrations. With South Dakota's Republican legislative majority and consistent voter emphasis on citizenship verification, traders assign a 97.7% implied probability of passage. Late shifts in turnout, an unusually effective opposition campaign, or unexpected polling movements among independents remain the primary variables that could alter the outcome before election day.