As of the census of 2000, there were 6,378 people, 2,330 households, and 1,589 families residing in the city. The population density was 655.7 people per square mile (253.1/km²). There were 2,545 housing units at an average density of 261.6/sq mi (101.0/km²). The racial makeup of the city was 79.23% White, 0.38% African American, 9.31% Native American, 0.14% Asian, 0.13% Pacific Islander, 7.53% from other races, and 3.29% from two or more races. Hispanic or Latino of any race were 19.22% of the population.
There were 2,330 households out of which 35.3% had children under the age of 18 living with them, 50.5% were married couples living together, 12.5% had a female householder with no husband present, and 31.8% were non-families. 27.6% of all households were made up of individuals and 11.5% had someone living alone who was 65 years of age or older. The average household size was 2.51 and the average family size was 3.06.
In the city the population was spread out with 26.6% under the age of 18, 10.7% from 18 to 24, 29.5% from 25 to 44, 20.2% from 45 to 64, and 13.0% who were 65 years of age or older. The median age was 34 years. For every 100 females there were 104.6 males. For every 100 females age 18 and over, there were 101.1 males.
The median income for a household in the city was USD $23,110, and the median income for a family was $29,509. Males had a median income of $46,845 versus $7,841 for females. The per capita income for the city was $14,750. About 34.6% of families and 37.4% of the population were below the poverty line, including 30.6% of those under age 18 and 35.7% of those age 65 or over.