As of the 2010 United States Census, there were 6,429 people, 2,832 households, and 1,823 families in the county. The population density was . There were 4,341 housing units at an average density of . The racial makeup of the county was 95.1% white, 2.1% American Indian, 0.4% black or African American, 0.2% Asian, 0.3% from other races, and 1.8% from two or more races. Those of Hispanic or Latino origin made up 1.3% of the population. In terms of ancestry, 47.0% were Norwegian, 37.4% were German, 7.7% were Irish, 6.2% were Swedish, and 1.4% were American.