N.J. Stat. § 19:15-6: Unofficial ballots; use permitted

If from any cause neither the official ballot nor ballots otherwise prepared as herein prescribed shall be ready for distribution at any polling place, or if the supply of ballots shall be exhausted before the polls are closed, unofficial ballots, made as nearly as possible in the form of the official ballot, may be used. The mode and manner of voting such unofficial ballots shall, nevertheless, in all respects conform as nearly as possible to the mode and manner of voting herein prescribed.