Washington state Democratic primary too early to call

The Democratic presidential primary in Washington state is too early to call.

All votes in Washington state are cast by mail or by dropping them off in a ballot box, and the state counts a significant amount on the day of the election.

But once that first update is released, election officials only provide an update once a day until all the late-arriving ballots are counted.

In the first batch of results released late Tuesday night, Bernie Sanders and Joe Biden are essentially tied — with each claiming about 33% of the roughly 1 million counted votes.

Most counties in Washington state will next provide an update about their results Wednesday.

WATCH: PBS NewsHour’s special coverage of the March 10 primaries

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