N.C. Gen. Stat. § 163-106.1
Eligibility to file.
§ 163-106.1. Eligibility to file.
No person shall be permitted to file as a candidate in a party primary unless that person has been affiliated with that party for at least 90 days as of the date of that person filing such notice of candidacy. A person registered as "unaffiliated" shall be ineligible to file as a candidate in a party primary election.