What issue did Stephen a Douglas believe had an constitutional basis its resolution?

Stephen A. Douglas believed that the issue of slavery had a constitutional basis in its resolution through popular sovereignty. He argued that the Constitution allowed territories to decide for themselves whether to allow slavery, thus advocating for the idea that residents of a territory should determine their own laws. This approach aimed to balance the interests of both pro-slavery and anti-slavery factions while upholding the principles of democracy and self-governance.