What you need to know about the Washington state primary

The Ballot: More than four million voters received a single ballot in the mail this month with both Republican and Democratic candidates. In order for the ballot to be valid and counted, voters can only pick one party and vote for one candidate. Election Night: Ballots must be postmarked Tuesday or dropped in an elections dropbox by 8 p.m. Tuesday. The state’s 39 counties will begin reporting numbers after 8 p.m. Tuesday. How Republican delegates are allocated: State Republicans will send 44 delegates to the July national convention. 30 will be allocated based on candidate percentages in the congressional districts - three per district. If a candidate gets more than 50 percent of the vote in a district, they get all three. If no candidate gets more than 50 percent and two candidates get more than 20 percent, the one with most gets two delegates. What Democrats do: Democrats ignore the results of the primary, instead allocating their delegates based on the state party’s caucus system. Sanders won the district caucuses on March 26. Following results of this past weekend’s congressional district caucuses, 74 delegates will go to Sanders and 27 to Clinton. Washington Democrats will send 17 superdelegates to the national convention. Why hold a primary if only one party uses the results and only one Republican candidate remains? State law requires the primary be held on the fourth Tuesday in May of a presidential year unless the Legislature cancels it. The Republican field was still crowded when the Legislature adjourned mid-April this year, so lawmakers would have to hold a special session to cancel the election.