According to the Associated Press Stylebook 2008, the U.S Census Bureau includes 16 states in the South region. The South region has three divisions: East South Central, West South Central and South Atlantic States.
East South Central: Alabama, Kentucky, Mississippi and Tennessee.
West South Central: Arkansas, Louisiana, Oklahoma and Texas.
South Atlantic: Delaware, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia and West Virginia.
Delaware is a southern state? I never knew . . .