According to the 2000 U.S. Census, the county has a total area of 506.30 square miles (1,311.3 km2), of which 490.34 square miles (1,270.0 km2) (or 96.85%) is land and 15.96 square miles (41.3 km2) (or 3.15%) is water.
There were 3,202 households out of which 29.10% had children under the age of 18 living with them, 61.30% were married couples living together, 6.50% had a female householder with no husband present, and 28.90% were non-families. 26.50% of all households were made up of individuals and 14.70% had someone living alone who was 65 years of age or older. The average household size was 2.44 and the average family size was 2.93.
In the county the population was spread out with 24.30% under the age of 18, 6.80% from 18 to 24, 24.10% from 25 to 44, 24.40% from 45 to 64, and 20.30% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 95.90 males. For every 100 females age 18 and over, there were 92.50 males.
The median income for a household in the county was $29,097, and the median income for a family was $33,651. Males had a median income of $26,092 versus $18,464 for females. The per capita income for the county was $14,254. About 9.30% of families and 13.40% of the population were below the poverty line, including 17.10% of those under age 18 and 13.10% of those age 65 or over.
Former GovernorMike Huckabee (R-Arkansas) received more votes, a total of 769, than any candidate from either party in Dade County during the 2008 presidential primary. He fell just 25 votes short from receiving the same amount of votes cast in the entire Democratic primary in Dade County.