Lincoln-Douglas Debates Expose Popular Sovereignty as Slavery Expansion Vehicle

The first of seven Lincoln-Douglas debates took place on August 21, 1858, in Ottawa, Illinois, as Republican challenger Abraham Lincoln faced Democratic Senator Stephen A. Douglas in a contest focused almost entirely on slavery’s expansion into the territories. The debates exposed fundamental conflicts over whether the Dred Scott decision and Kansas-Nebraska Act represented efforts to nationalize slavery throughout the United States. Lincoln argued against slavery expansion while stressing he was not advocating abolition where it already existed, emphasizing “the moral iniquity of slavery” and attacking popular sovereignty for the bloody results it had produced in Kansas. Douglas defended his doctrine of “popular sovereignty,” declaring that territorial settlers should decide whether to permit slavery as a matter of local self-governance.

At Freeport, Lincoln challenged Douglas to reconcile popular sovereignty with the Dred Scott decision, which declared that Congress could not prohibit slavery in territories. Douglas’s response—known as the Freeport Doctrine—held that settlers could circumvent the Supreme Court by refusing to establish the local “slave code” regulations protecting masters’ property rights. This position antagonized Southern Democrats who supported slavery, since it raised the possibility that slavery might not extend into territories despite the Court’s ruling. The Freeport Doctrine caused a major rift in the Democratic Party between Southern members who viewed it as betrayal and Northern Democrats who saw it as necessary political accommodation.

Douglas won the immediate contest, with Democrats gaining 46 legislative seats to the Republicans’ 41 (state legislatures then elected senators). However, the debates propelled Lincoln into the national spotlight while simultaneously damaging Douglas’s political career by alienating Southern Democrats. The debates foreshadowed the 1860 presidential election, where the Democratic split between Douglas’s Northern faction and Southern pro-slavery Democrats enabled Lincoln’s victory with only 39 percent of the popular vote. The debates demonstrated that popular sovereignty, rather than being a democratic solution to the slavery question, had become a vehicle for slavery expansion that deepened sectional divisions and accelerated the nation toward Civil War.