Geography According to the U.S. Census Bureau, the county has a total area of 5,306 km² (2,049 mi²). 5,276 km² (2,037 mi²) of it is land and 30 km² (12 mi²) of it is water. The total area is 0.57% water.
Demographics As of the census of 2000, there are 20,107 people, 7,153 households, and 5,250 families residing in the county. The population density is 4/km² (10/mi²). There are 8,014 housing units at an average density of 2/km² (4/mi²). The racial makeup of the county is 76.73% White, 0.71% African American, 1.24% Native American, 0.56% Asian, 0.10% Pacific Islander, 18.11% from other races, and 2.55% from two or more races. 29.86% of the population are Hispanic or Latino of any race.
There are 7,153 households out of which 39.00% have children under the age of 18 living with them, 61.50% are married couples living together, 7.50% have a female householder with no husband present, and 26.60% are non-families. 21.20% of all households are made up of individuals and 8.20% have someone living alone who is 65 years of age or older. The average household size is 2.75 and the average family size is 3.19.
In the county, the population is spread out with 28.80% under the age of 18, 12.70% from 18 to 24, 29.10% from 25 to 44, 19.20% from 45 to 64, and 10.20% who are 65 years of age or older. The median age is 30 years. For every 100 females there are 105.90 males. For every 100 females age 18 and over, there are 106.90 males.
The median income for a household in the county is $35,872, and the median income for a family is $42,226. Males have a median income of $26,991 versus $20,404 for females. The per capita income for the county is $15,692. 14.10% of the population and 10.20% of families are below the poverty line. Out of the total people living in poverty, 17.80% are under the age of 18 and 7.40% are 65 or older.