N.M. Stat. § 1-6C-5
Random identifier and verification code.
A. Prior to each election, the administrator shall assign to each voter-participant eligible to
vote in that election a random identifier and a verification code for use in that election only.
B. In the mailed absentee ballot or mailed ballot process, the random identifier shall be used
in place of the voter-participant's required voter identification and the verification code shall be
used in place of the voter-participant's signature.
C. At the same time a ballot is mailed to a voter-participant, the administrator shall
separately send the voter-participant the verification code assigned to the voter-participant for
that election, along with instructions to place the verification code where a voter normally
provides a signature under the privacy flap of a mailed absentee ballot or mailed ballot.