Why were the Bolsheviks successful in October 1917?

Introduction The October Revolution was led by the Bolsheviks under the leadership of Vladimir Lenin and Leon Trotsky and marked the first officially Communist revolution of the twentieth century, based upon the ideas of Karl Marx. The crucial revolutionary activities in Petrograd were under the command of the Petrograd Soviet headed by Leon Trotsky and the Military Revolutionary Committee headed by Adolph Joffe. The revolution was widely regarded as a reaction to the strains that …

…clear note sounded day after day, the deepening chorus of the Bolsheviki, "All Power to the Soviets! All power to the direct representatives of millions on millions of common workers, soldiers, peasants" * "When an unqualified majority of the workers and soldiers of Petrograd had come over to the Bolsheviks, the boiling temperature, it seemed, was reached. It was then that Lenin proclaimed the necessity of immediate insurrection". Leon Trotsky's The History of the Russian Revolution