Colorado Revised Statutes Title 1. Elections § 1-13.5-1006. Manner of absentee voting by paper ballot

(1) Any eligible elector applying for and receiving an absentee voter's ballot, in casting the ballot, shall make and subscribe to the self-affirmation on the return envelope. The voter shall then mark the ballot. The voter shall fold the ballot so as to conceal the marking, deposit it in the return envelope, and seal the envelope securely. The envelope may be delivered personally or mailed by the voter to the designated election official issuing the ballot. It is permissible for a voter to deliver the ballot to any person of the voter's own choice or to any duly authorized agent of the designated election official for mailing or personal delivery to the designated election official. To be counted, all envelopes containing absentee voter's ballots must be in the hands of the designated election official or an election judge for the local government not later than 7 p.m. on election day.

(2) Upon receipt of an absentee voter's ballot, the designated election official or an election judge shall write or stamp on the envelope containing the ballot the date and hour that the envelope was received and, if the ballot was delivered in person, the name and address of the person delivering the same. The designated election official or election judge shall safely keep and preserve all absentee voter's ballots unopened until the time prescribed for delivery to the judges as provided in section 1-13.5-1008.