Those who do not learn from the mistakes of history are doomed to repeat them.

From Wikipedia, under "Nazi Party":

"Depressed working-class areas such as Thuringia also gave a strong Nazi vote, while the workers of the Ruhr and Hamburg largely remained loyal to the SPD, the KPD or the Catholic Centre Party. Nuremberg remained a party stronghold, and the first Nuremberg rally was held there in 1927. These rallies soon became massive displays of Nazi paramilitary power, and attracted many recruits. The Nazis' strongest appeal was to the lower middle-class – farmers, public servants, teachers, small businessmen – who had suffered most from the inflation of the 1920s and who feared Bolsheviks more than anything else. The small business class were receptive to Hitler's anti-Semitism, since they blamed Jewish big business for their economic problems. University students, disappointed at being too young to have served in World War I and attracted by the Nazis' radical rhetoric, also became a strong Nazi constituency.

Despite these strengths, the Nazi Party might never have come to power had it not been for the Great Depression and its effects on Germany. By 1930 the German economy was beset with mass unemployment and widespread business failures. The SPD and the KPD parties were bitterly divided and unable to formulate an effective solution; this gave the Nazis their opportunity, and Hitler's message, blaming the crisis on the Jewish financiers and the Bolsheviks resonated with wide sections of the electorate."

And let's play MadLibs...what I'm gonna do is swap no more than 10 words, adjust the syntax so the sentences make sense, and see what happens.

"Depressed working-class area also gave a strong Obama vote, while the workers of corporations and self-employed professionals largely remained loyal to Bush. Chicago remained a party stronghold, and the first Grant Park rally was held there in 2008. These rallies soon became massive displays of Obama's paramilitary power, and attracted many recruits . Obama's strongest appeal was to the lower middle-class – farmers, public servants, teachers, small businessmen – who had suffered most from the inflation of the 2000s and who feared Republicans more than anything else. The small business class were receptive to Obama's anti-Bush rhetoric, since they blamed Republican big business for their economic problems. University students, disappointed at being too young to have served in Iraq or Afghanistan and attracted by Obama's radical rhetoric, also became a strong Obama constituency.

Despite these strengths, Obama might never have come to power had it not been for the 2008 Economic recession and its effects on America. By 2008 the American economy was beset with mass unemployment and widespread business failures. The Republican and Democratic parties were bitterly divided and unable to formulate an effective solution; this gave Obama his opportunity, and Obama'ss message, blaming the crisis on the Republican financiers and the upper class resonated with wide sections of the electorate."

P.S. Contrary to every liberal mind (oxymoron) on the planet, this does not make me a racist. It makes me studied in history and concerned about my country. Mass hysteria-induced crowds, drunk on "hope" never did any good for anybody. Last time a little place called "Europe" was decimated.