We elected a conservative governor as late as 1986, when George Deukmejian won re-election. However, Tom McClintock's defeat in his bid for lieutenant governor may be an indication that California has passed the "tipping point" and will be a "blue state" for the forseeable future.
I have not been to California much, but in my opinion the best way to elect a conservative Republican statewide in California would be to run a conservative Hispanic Republican based on social issues. RINO Republicans would be opposed because of the issues, and the Hispanics may be more concerned about immigration and economic left wing issues at this time, but the day may come!!