Sanders overwhelmingly won the March 26 caucus which had about 230,000 participants, winning 72.7% of the state's legislative district delegates to Clinton's 27.1%, giving Sanders a net gain of 47 pledged delegates.

His victory did not come as a huge surprise, since Seattle as a city had donated the most money per capita to the Bernie Sanders for President Campaign, and Washington state (particularly Seattle) has a history of electing more left-leaning politicians including other self-proclaimed socialists to office.

Clinton had lost the Washington caucus eight years earlier to Barack Obama.

[8] At a rally in Wisconsin on March 26, Sanders told supporters "We knew from day one that politically we were going to have a hard time in the Deep South, but we knew things were going to improve when we headed west.

For the 2020 nominating process, Washington and Nebraska both replaced their caucuses with binding primaries to allocate the states' delegates.