As of the census of 2000, there were 107,120 people, 41,599 households, and 25,583 families residing in the county. The population density was 237 people per square mile (91/km²). There were 43,479 housing units at an average density of 96 per square mile (37/km²). The racial makeup of the county was 94.2% White, 1.1% Black or African American, 2.41% Native American, 3.15% Asian, 0.02% Pacific Islander, 0.27% from other races, and 1.03% from two or more races. 0.92% of the population were Hispanic or Latino of any race. 38.9% were of German, 20.3% Norwegian and 7.9% Irish ancestry according to Census 2000. 94.8% spoke English, 1.8% Hmong and 1.7% Spanish as their first language.
There were 41,599 households out of which 29.90% had children under the age of 18 living with them, 50.00% were married couples living together, 8.40% had a female householder with no husband present, and 38.50% were non-families. 28.40% of all households were made up of individuals and 9.80% had someone living alone who was 65 years of age or older. The average household size was 2.45 and the average family size was 3.02.
In the county, the population was spread out with 23.60% under the age of 18, 15.60% from 18 to 24, 27.50% from 25 to 44, 20.80% from 45 to 64, and 12.50% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 94.10 males. For every 100 females age 18 and over, there were 90.70 males.