For your vote to count, you must vote for one candidate from the political party you marked on your envelope. If you do not indicate your party, your vote will not be counted. Your party selection will be removed from your voter record 60 days after certification of the Presidential Primary.
For Washington’s primary, make sure to get your ballots postmarked or dropped in a ballot box by 8 p.m. on March 12th. If you haven't registered to vote yet, there's still time! You can register online or by mail until March 4th, and in person until March 12th.
https://clark.wa.gov/elections/march-12-presidential-primary-voter-registration-deadlines