As of the 2010 United States Census, there were 3,821 people, 1,657 households, and 1,041 families living in the county. The population density was . There were 1,880 housing units at an average density of . The racial makeup of the county was 90.3% white, 4.7% American Indian, 0.4% black or African American, 0.4% Asian, 0.1% Pacific islander, 1.6% from other races, and 2.4% from two or more races. Those of Hispanic or Latino origin made up 3.3% of the population. In terms of ancestry, 39.4% were German, 16.7% were English, 16.5% were Irish, and 3.0% were American.