The GOP-majority North Carolina Board of Elections approved stricter rules for mail-in ballots Friday, just hours before the state became the first in the country to begin sending ballots for the midterm elections.

The State Board of Elections voted along party lines to direct county officials to reject certain absentee ballots for certain errors that previously would not have prevented a vote from being counted. Republican board members said the changes are necessary to enforce state election law, while Democrats warned they could bar otherwise eligible voters from casting their ballots.