Fact: until the ANCSA generation came long and the influence of folks like Willie Hensley, Eben Hopson and Byron Mallott shifted things solidly towards the Democrats, Natives tended to be Republican.  The involvement of Natives in the white man's electoral politics began in the 1920s with Republican William Paul.  Even within the ANCSA generation, there were quite a number of Koyukon and other closely related Athabaskans who are / were Republican (e.g. John Sackett, Morris Thompson, Jules Wright).