How did the Kansas-Nebraska Act affect the amount of land that was open to slavery?
It allowed for the possibility of new slave states.
The Kansas-Nebraska Act allowed people in the territories of Kansas/Nebraska to vote whether or not slavery should be allowed. This idea is known as popular sovereignty. Knowing this, many pro-slavery and many anti-slavery citizens flocked to the region to vote. Because of their differences, people fought over the idea of slavery. As a result, Kansas earned the name "Bleeding Kansas".