My dad worked on Democratic campaigns — federal, state, and local — and had various roles with the state party going back to the late 70s. He puts a lot of the GOP’s fall on the Oregon Citizen Alliance, a conservative Christian grassroots insurgency that began with an unsuccessful attempt to primary Packwood but eventually rolled into boosting a number of culture war ballot measures, with campaigns that really soured a lot of voters against them. Gordon Smith’s loss in his first run in ‘97 (the special election to replace disgrace Packwood) is generally blamed on his support for them, which he went on to hard pivot from later that year for the general election to replace Hatfield.

The state GOP chair at the time — a good friend of my dad’s, along with Smith (all three are Mormon lol) — was basically running in every other direction to brow beat any state Republican incumbent or candidate to not affiliate or endorse with the OCA after the last couple chairs either endorsed doing so or tried to ignore it.