Casco Township was established in 1854 by the division of Ganges Township.[citation needed] New Casco was the name of a post office here starting on December 8, 1856.[18][19] In 1876, the New Casco post office was renamed Glenn on May 15, 1876.[18] A post office operated at Hawkhead from March 23, 1882, to January 31, 1902.[10]
According to the United States Census Bureau, the township has a total area of 39.0 square miles (100.9 km2), of which 38.9 square miles (100.7 km2) is land and 0.077 square miles (0.2 km2), or 0.17%, is water.[20]
As of the census[1] of 2000, there were 3,019 people, 1,083 households, and 794 families residing in the township. The population density was 77.7 inhabitants per square mile (30.0/km2). There were 1,827 housing units at an average density of 47.0 per square mile (18.1/km2). The racial makeup of the township was 88.14% White, 3.41% African American, 0.70% Native American, 0.40% Asian, 5.47% from other races, and 1.89% from two or more races. Hispanic or Latino of any race were 11.39% of the population.
There were 1,083 households, out of which 30.3% had children under the age of 18 living with them, 61.8% were married couples living together, 6.9% had a female householder with no husband present, and 26.6% were non-families. 22.4% of all households were made up of individuals, and 8.7% had someone living alone who was 65 years of age or older. The average household size was 2.63 and the average family size was 3.05.
In the township the population was spread out, with 25.8% under the age of 18, 8.3% from 18 to 24, 26.8% from 25 to 44, 26.9% from 45 to 64, and 12.2% who were 65 years of age or older. The median age was 38 years. For every 100 females, there were 107.1 males. For every 100 females age 18 and over, there were 106.7 males.
The median income for a household in the township was $45,043, and the median income for a family was $49,821. Males had a median income of $36,935 versus $27,412 for females. The per capita income for the township was $22,356. About 4.3% of families and 8.5% of the population were below the poverty line, including 9.0% of those under age 18 and 2.3% of those age 65 or over.