Final answer:
Blacks in the South were disenfranchised through poll taxes, literacy tests, and physical intimidation. The NAACP organized voting efforts in Mississippi.
Step-by-step explanation:
In many of the South's districts, especially rural ones, blacks were effectively disenfranchised by poll taxes, literacy tests, and physical intimidation put in place by the white majority. The NAACP (National Association for the Advancement of Colored People) organized voting efforts in Mississippi to combat these voter suppression tactics.