[2] On March 16, 2020, almost a week after the primary, major news outlets including CNN, NBC, The New York Times, and the Associated Press called the narrow race for former vice president Joe Biden, who won 37.9% of the vote and 46 delegates, around 20,000 votes ahead of senator Bernie Sanders.

Sanders reached 36.6% of the vote and received 43 delegates, adding another crucial loss to his campaign, while a win, widely expected in polls, had been seen as vital for him to remain a realistic contender for the presidential nomination.

Washington was one of six states (along with Democrats Abroad) which held primaries on March 10, 2020, one week after Super Tuesday.

In the primary, candidates had to meet a threshold of 15 percent at the congressional district or statewide level to be considered viable.

The 89 pledged delegates to the 2020 Democratic National Convention were allocated proportionally on the basis of the results of the primary.