The primary election is only for voters who are affiliated with a political party.
Presidential candidates are not on the ballots.
The June 26 primary is mostly about picking candidates to be on the ballot for state-level offices.
If you want to switch to or join a political party, you have until Tuesday to do so.
If you have a Colorado driver's license or ID card, you can do that online here, http://www.sos.state.co.us/pubs/elections/vote/VoterHome.html or you can call your county clerk Tuesday for help.
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