Mont. Code Ann. § 13-12-102

The election administrators shall deliver to each polling place or to the chief election judge for a polling place all supplies necessary to conduct the election at that polling place. If the blank ballots for the polling place are delivered before noon of the day before the election, the election administrator shall retain sufficient ballots to supply electors requesting absentee ballots. The election administrator shall write in the pollbook for that polling place, after the numbers of the ballots retained, "reserved for absentee ballots".