There are several reasons to support this. Back in the 1950's and 60's, the high unemployment rate equated to high Democratic backing. The democratic backing rose significantly as more and more issues surfaced. State Legislation which were controlled by the democrats redrew congressional district maps.
This made it difficult for the Republicans to win House seats. Up until the 90's till today, it is evident that democrats tend to do better in low-turnout districts as compared to the republicans who tend to do well in high-turnout district and thus, dominate congress. According to very many political science evidence, till date, suggest that electoral system has no partisan bias.
Serving an expanded citizenry, Reconstruction governments established the South’s first state-funded public school systems, sought to strengthen the bargaining power of plantation labourers, made taxation more equitable, and outlawed racial discrimination in public transportation and accommodations. They also offered lavish aid to railroads and other enterprises in the hope of creating a “New South” whose economic expansion would benefit Blacks and whites alike.
Some of the diseases were new and treatments were ineffective. Malaria was deadly to many new colonists, especially in the Southern colonies. Of newly arrived men, over one-fourth of the Anglican missionaries died within five years of their arrival in the Carolinas. Mortality was high for infants and small children, especially for diphtheria, small pox, yellow fever, and malaria.
On mine it’s b but if not I am so sorry