Analyze the reasons for and the results of transformations in American political parties during the ...

Answer: Economic prosperity and standardization of political procedures diminished party differences, and loyalty, by the 1850s. The Whig party disintegrated because of its inability to cope with the slavery issue. The Democrats, led by Stephen Douglas, hoped to please everyone with such measures as the Kansas-Nebraska Act, and ended by pleasing no one. The short-lived Know-Nothings represented a cyclical nativist reaction. The Republicans opposed expansion of slavery to the new territories and steadily won influence in the North.