(AP) — State statistics show that four times as many prospective Kansas voters have their registrations on hold for failing to meet a proof-of-citizenship requirement than for all other reasons combined.

Kansans with registrations on hold can’t legally cast ballots. A law that took effect in January requires new Kansas voters to produce a birth certificate, passport or other papers documenting their U.S. citizenship.

Election officials also put registrations on hold for other reasons. It happens when people fill out registration forms improperly or register before turning 18.

Kansas has more than 21,000 voter registrations on hold. More than 17,000 — or 80 percent of the total — were for people who hadn’t yet met the proof-of-citizenship requirement. The secretary of state’s office provided the figures to The Associated Press.