The Spanish Civil War between fascism and elected leaders was won by the

Nationalists.

Explanation:

Spanish Civil War was a military revolt that started in 1936 by a conservative faction against Spain's republican government. The war is sometimes portrayed as a battle between fascism and democracy. Where rebels or nationalists under the leadership of General Francisco Franco got aid from fascist forces of Germany and Italy. On the other hand, Republicans who leaned towards democracy received aid from European sympathizers and the United States. Finally, the Nationalists section won, and Franco became ruler of Spain from April 1939 until he died in 1975.

confedracy

supported slavery

upheld the supremacy of federal laws

believed states should be able to nullify federal laws

union

wanted to abolish slavery

supported high tariffs

upheld the supremacy of federal laws