Lamar is a Home Rule Municipality that is the county seat and the most populous municipality of Prowers County, Colorado, United States. The city population was 7,804 at the 2010 United States Census. The city was named after Lucius Quintus Cincinnatus Lamar II during the period that he was Secretary of the Interior in the futile hope that the then town would be named as the land office.
As of the census of 2010, there were 7,804 people, 3,102 households, and 1,980 families residing in the city. The population density was 1,858.1 people per square mile (717.4/km²). There were 3,666 housing units at an average density of 872.9/sq mi (337.0/km²). The racial makeup of the city was 78.6% White, 0.7% African American, 1.0% Native American, 0.4% Asian, 0.0% Pacific Islander, 16.3% from other races, and 3.0% from two or more races. Hispanic or Latino of any race were 39.7% of the population.
There were 3,102 households out of which 42.2% were married couples living together, 15.8% had a female householder with no husband present, and 36.2% were non-families. 31.8% of all households were made up of individuals living alone and 12.8% had someone living alone who was 65 years of age or older. The average household size was 2.43 and the average family size was 3.07.
In the city, the population was spread out with 27.8% under the age of 18, 10.4% from 18 to 24, 23.4% from 25 to 44, 24.3% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 34.1 years. For every 100 females, there were 93.7 males. For every 100 females age 18 and over, there were 88.8 males.
The median income for a household in the city was $31,521, and the median income for a family was $43,588. Males working full-time and year-round had a median income of $31,621 versus $30,148 for females. The per capita income for the city was $16,944. About 21.4% of families and 24.6% of the population were below the poverty line, including 34.1% of those under age 18 and 15.1% of those age 65 or over.