III.

The Period of North-South Conflict

A voter backlash severely changed the party’s fortunes in the mid-1850s. The Democratic commitment to limited national power extended to the question of whether or not slavery should expand into new territories. Party leaders such as Lewis Cass and Stephen A. Douglas favored local control, or popular sovereignty, rather than congressional regulation. This did not satisfy some party supporters and others outside the party. Southern gains in the territories provoked bitter anger. At the same time, the Democrats’ long-standing interrelationship with immigrant workers also caused severe problems. Greatly increased immigration in the 1850s transformed many areas of the country and seemed to threaten American values. The result was an electoral disaster, as many northern Democrats, seeking to punish their leaders and willing to throw aside their party, joined the emerging Republicans. These defections cost the party a large part of its northern support and enhanced the power of the southern wing within party councils in the late 1850s.