Colorado Revised Statutes Title 1. Elections § 1-9-207. Challenges of ballots cast by mail

(1) The ballot of any elector that has been cast by mail may be challenged using a challenge form signed by the challenger under penalty of perjury setting forth the name of the person challenged and the basis for the challenge. Challenged ballots, except those rejected for forgery of a deceased person's signature on a mail ballot affidavit or submission of multiple ballots, must be counted. The election judges shall forthwith deliver all challenges, together with the affidavits of the persons challenged, to the county clerk and recorder or designated election official, as applicable.

(2) A mail ballot may not be challenged under this section solely on the basis of the signature that appears on the mail ballot. Signatures on mail ballots must be reviewed in accordance with section 1-7.5-107.3.