The two-term superintendent had been mulling a challenge to Democratic incumbent Jay Inslee and said he was "push button" ready to announce his candidacy as late as last week before eventually deciding against it.
Dorn's main aim would have been meeting the state Supreme Court's 2012 McCleary decision on education funding, and he has criticized Inslee for his leadership in education funding.
Though Dorn didn't endorse either gubernatorial candidate Thursday, he said he would bet on Inslee "having a better vision and idea for what needs to be done" to satisfy the Supreme Court.
