The topic of slavery is rather sensitive to cover, however there is no doubting that it had a vast impact on white American southerners, both rich and poor.
A by-product of the cotton gin saw a rise in supply and demand in the slave trade in the south. New advancements allowed for an easier harvest of crops. Through this, slavery greatly expanded and in turn there was a sharp rise in profits for plantation owners.
At this time, there was skewed ownership of slaves in the South, being that poorer Southerners did not have any slaves whilst the rich possessed many. Those with large plantations held the most esteem and power in the south, however this percentage remained very small throughout. Only approximately 30% of southerners owned slaves between 1790-1840.
Those who could not afford slaves were not against slavery. They were inspired by their peers, working hard on small farms with aspirations of owning slaves of their own one day. In other words, whilst the quantifiable possession of slaves was divided in the south, the mentality, attitude and racial philosophy was greatly unified and unanimous at this time.
So in short, the impact of slavery in the south was economic development and financial gain for the rich, and aspirations for the poor, along with a unified mentality. Clearly, there was no leeway for any racial nuances since the south, in general, was strongly pro slavery and thus the debasement of the 'slave' race.