The Bull Moose Party (also called the Progressive Party) was started by Theodore Roosevelt in 1912, just after the Republican Party has split up between Roosevelt and Howard Taft.
Explanation:
America's involvement in World War II had a significant impact on the economy and workforce of the United States. American factories were retooled to produce goods to support the war effort and almost overnight the unemployment rate dropped to around 10%.
It offered an escape from the pressure of factory work.