100,000 new members in the next few months following the election. Well over one million pamphlets were produced and distributed; sixty trucks were commandeered for use in Berlin alone. In areas where Nazi campaigning was less rigorous, the total share of the vote was as low as 9%. The Great Depression was also a factor in Hitler's electoral success. Against this legal backdrop, the SA began its first major anti-Jewish action on 13 October 1930, when groups of Nazi brownshirts smashed the windows of Jewish-owned stores at Potsdamer Platz. Weimar parties fail to halt Nazis The Wall Street Crash of 1929 heralded worldwide economic disaster. The Nazis and the Communists made great gains at the 1930 federal election. The Nazis and Communists between them secured almost 40% of Reichstag seats, which required the moderate parties to consider negotiations with anti-democrats. "The Communists", wrote historian Alan Bullock, "openly announced that they would prefer to see the Nazis in power rather than lift a finger to save the republic". It turned out that The Weimar political parties failed to stop the Nazi rise. Germany's Weimar political system made it difficult for chancellors to govern with a stable parliamentary majority, and successive chancellors instead relied on the president's emergency powers to govern. From 1931 to 1933, the Nazis combined terror tactics with conventional campaigning – Hitler criss-crossed the nation by air, while SA troops paraded in the streets, beat up opponents, and broke up their meetings. Systematic statistical analyses demonstrate that voters responded the way they do in most modern elections, which explains why certain identifiable groups turned to the Nazis and others turned away. A middle-class liberal party strong enough to block the Nazis did not exist – the People's Party and the Democrats suffered severe losses to the Nazis at the polls. The Social Democrats were essentially a conservative trade union party, with ineffectual leadership. The Catholic Centre Party maintained its voting block, but was preoccupied with defending its own particular interests and, wrote Bullock: "through 1932–3 ... was so far from recognizing the danger of a Nazi dictatorship that it continued to negotiate with the Nazis". The Communists meanwhile were engaging in violent clashes with Nazis on the streets, but Moscow had directed the Communist Party to prioritise destruction of the Social Democrats, seeing more danger in them as a rival for the loyalty of the working class. Nevertheless, wrote