Despite the margin of victory, Culp refused to concede and filed a lawsuit against Republican Washington Secretary of State Kim Wyman five weeks after the election.

These included Attorney General Bob Ferguson, Commissioner of Public Lands Hilary Franz and King County executive Dow Constantine.

[15][16] Several Republican politicians announced their own campaigns to challenge Inslee, including businessman Anton Sakharov, Republic police chief Loren Culp, and state senator Phil Fortunato.

[17][18][19] However, speculated candidates such as former U.S. Representative Dave Reichert, former Seattle Port Commissioner and 2016 gubernatorial nominee Bill Bryant, Pierce County Executive and former state senator Bruce Dammeier, and state House Minority Leader J. T. Wilcox, all declined to be candidates, leaving no prominent Republicans to challenge Inslee, which was seen as a necessary prerequisite to mount a formidable challenge to him.

Washington is one of two states that holds a top-two primary, meaning that all candidates are listed on the same ballot regardless of party affiliation, and the top two move on to the general election.