[3] Incumbent Democratic senior Senator Patty Murray ran for re-election to a fifth term in office,[9] defeating Republican challenger Chris Vance by 18 points.

[10] Incumbent Governor Jay Inslee was re-elected to his second term over Port of Seattle Commissioner Bill Bryant.

[17][18] Four Democrats (three of whom were state senators), four Republicans, two third-party candidates, and one independent competed in the primary election.

[1] Incumbent Secretary of State Kim Wyman, elected in 2012 as the only Republican to hold a statewide office on the West Coast, sought reelection.

[23] Former Seattle City Councilmember Tina Podlodowski announced her bid in January 2016, seeking to become the first Democrat to hold the office since 1965.

Mark Miloscia (R) and Pat McCarthy (D) finished as top two and advanced to the general election.

[29] Five candidates ran to succeed him: state senator Marko Liias, former Port of Seattle commissioner Alec Fisken, pension consultant John Paul Comerford, Benton County treasurer Duane Davidson, and investment firm executive Michael Waite.

[30] Duane Davidson and Michael Waite, both Republicans, finished as top two in the primary election and advanced to the general election, marking the first time since the top-two system had been instituted that both of the primary slots in any statewide race had been won by Republicans.

Erin Jones and Chris Reykdal finished as top two and advanced to the general election.

[1] Seven incumbent senators retired, creating vacancies that had the potential to swing the split of party votes.