In 1860 90% of the country was indifferent or pro slavery. Pro slavery was the conservative position. If you view the mid 19th century thru a 21st century lens you will get a distorted view of things.
Self-respect and the ability to care for oneself is extremely important. Dependency weakens the mind, the body and the soul. If you read the so-called declarations of secession that the slaveholders drafted, you will see that the slaveholders themselves were well aware of their dependency on slaves and believed that they could not go forward in this world without being cared for by slaves. It seems that they were quite aware that they had through generations of slavery created in themselves a "culture of dependency" akin to an addiction.
Lincoln freed them of all that and that's why their descendants are now grateful.
In 1860 the pro-slavery types were southerners - virtually all democrats. Nothing conservative about them at all.
And yet the Republican party's appeal in 1860--indeed their founding principle-- was opposition to slavery and Lincoln won with a solid plurality of the popular vote and a handy majority of the electoral vote. For being largely indifferent at best to slavery, voters sure did turn out to vote for the anti-slavery candidate.