If you are a member of a specific party, you are allowed to only vote in that party's primary. Example: Someone who is a registered Republican may only vote in the Republican Primary. If you are "Unaffiliated" then NC does allow you to choose which political party's primary you would like to vote in, or you may opt to vote an Unaffiliated ballot. Once your vote is cast, you may not change it. No one, regardless of their affiliation, can vote in more than one primary.