Is there any way - we've not found one, but maybe exists - to track changes in Oregon party affiliation? Would be highly interesting to track.
As it is, we just have case by case. An intriguing one today in the Eugene Register Guard, which notes that one of the top Republican state Senate candidates of 2006 - former Eugene Mayor Jim Torrey - recently has changed party affiliation from Republican to Independent (as in, the Independent Party of Oregon, the one under whose banner John Frohnmayer is running for the U.S. Senate).
Torrey said he has no plans to run statewide for any office.