Final answer:
During the 1848 presidential election, the Democratic and Whig parties avoided the issue of slavery to maintain party unity and to balance between their northern and southern constituents. The issue threatened to fracture their diverse coalitions of voters and overshadowed other issues due to economic prosperity that made concerns like tariffs less pressing. The parties employed strategic ambiguity, presenting candidates with moderate views on slavery to prevent voter alienation.
Step-by-step explanation:
The Democratic and Whig parties avoided confronting the issue of slavery during the 1848 presidential election for several reasons. Firstly, slavery was a contentious issue that deeply divided the nation along geographical lines, threatening party unity. Both the Democrats and the Whigs were coalitions of diverse voters, and maintaining their support was crucial to winning national elections. The Whigs and Democrats had to balance between their northern and southern supporters, leading to them running different campaigns in these regions. Secondly, economic prosperity at the time reduced public concern about other major issues such as the tariff, national bank, or internal improvements, turning the focus unintentionally towards slavery.
Furthermore, the Democrats promoted the concept of popular sovereignty, which allowed territories to decide the legality of slavery amongst themselves, while the Whigs did not unify on a single position. Both parties chose candidates, Lewis Cass for the Democrats and General Zachary Taylor for the Whigs, who had moderate stances on slavery to not alienate any portion of their electorate. The emergence of the Free Soil Party, which opposed the extension of slavery into territories, forced the major parties to address the issue indirectly due to its popularity in the northern states.
At the core, the avoidance was a strategic decision to prevent the alienation of any particular group within their diverse supporter base, and an attempt to maintain party unity in the face of an increasingly divisive issue. This led to a delicate balancing act where slavery was concerned, contributing to the complexity of the political landscape of the time.