The Washington State Senate elections were held on November 2, 2010, in which about half of the state's 49 legislative districts choose a state senator for a four-year term to the Washington State Senate. The other half of state senators are chosen in the next biennial election, so that about half of the senators, along with all the members of the Washington State House of Representatives, are elected every two years.
24 seats were regularly scheduled to be up this cycle, along with 1 additional seat holding a special election to fill an unexpired term: the 28th district, held by appointed Senator Steve Litzow, whose former incumbent Fred Jarrett vacated the seat.
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