|• Total||2.2 sq mi (5.7 km2)|
|• Land||2.1 sq mi (5.5 km2)|
|• Water||0.1 sq mi (0.2 km2)|
|Elevation||856 ft (261 m)|
|• Density||2,600/sq mi (1,000/km2)|
|Time zone||UTC-5 (Eastern (EST))|
|• Summer (DST)||UTC-4 (EDT)|
|GNIS feature ID||0610417|
Spencer is located at (42.243276, -71.99437).
According to the United States Census Bureau, the CDP has a total area of 5.7 km² (2.2 mi²). 5.5 km² (2.1 mi²) of it is land and 0.2 km² (0.1 mi²) of it (2.74%) is water.
As of the census of 2000, there were 6,032 people, 2,554 households, and 1,527 families residing in the CDP. The population density was 1,093.4/km² (2,835.2/mi²). There were 2,722 housing units at an average density of 493.4/km² (1,279.4/mi²). The racial makeup of the CDP was 97.58% White, 0.61% Black or African American, 0.31% Native American, 0.28% Asian, 0.02% Pacific Islander, 0.41% from other races, and 0.78% from two or more races. Hispanic or Latino of any race were 1.61% of the population.
There were 2,554 households out of which 29.8% had children under the age of 18 living with them, 42.8% were married couples living together, 12.5% had a female householder with no husband present, and 40.2% were non-families. 33.0% of all households were made up of individuals and 13.5% had someone living alone who was 65 years of age or older. The average household size was 2.35 and the average family size was 2.98.
In the CDP, the population was spread out with 24.4% under the age of 18, 9.9% from 18 to 24, 30.7% from 25 to 44, 20.9% from 45 to 64, and 14.1% who were 65 years of age or older. The median age was 35 years. For every 100 females, there were 91.8 males. For every 100 females age 18 and over, there were 89.3 males.
The median income for a household in the CDP was $35,206, and the median income for a family was $46,333. Males had a median income of $36,563 versus $25,738 for females. The per capita income for the CDP was $18,975. About 9.0% of families and 12.0% of the population were below the poverty line, including 16.6% of those under age 18 and 11.7% of those age 65 or over.