USA HISTORY

Detailed explanation-1: -After the primaries and caucuses, each major party, Democrat and Republican, holds a national convention to select a Presidential nominee.

Detailed explanation-2: -In 1854, the Republican Party emerged to combat the expansion of slavery into American territories after the passing of the Kansas–Nebraska Act. The early Republican Party consisted of northern Protestants, factory workers, professionals, businessmen, prosperous farmers, and after the Civil War, former black slaves.