Colo. Rev. Stat. § 1-13.5-306
All self-nomination and acceptance forms or letters, petitions of nomination, and affidavits of intent to be a write-in candidate that are in apparent conformity, as determined by the designated election official, with section 1-13.5-302, 1-13.5-303, or 1-13.5-305, are valid unless objection thereto is duly made in writing within three days after the filing of the same. In case an objection is made, the designated election official shall mail forthwith notice of the objection to any candidate for the same office. The designated election official shall decide objections within forty-eight hours after the same are filed, and any objections upheld may be remedied or defect cured upon the original petition, by an amendment thereto, or by filing a new self-nomination and acceptance form or letter, petition of nomination, or affidavit of intent, as applicable, within three days after the objection is upheld, but in no event later than the fifty-eighth day before the day of election. The designated election official shall pass upon the validity of all objections, whether of form or substance, and the designated election official's decisions upon matters of form are final. The designated election official's decisions upon matters of substance are open to review if prompt application is made, as provided in section 1-13.5-1501, but the remedy in all cases shall be summary, and the decision of the district court is final and not subject to review by any other court; except that the supreme court, in the exercise of its discretion, may review any proceeding in a summary way.
C.R.S. § 1-13.5-306