How did Lenin contribute to the Russian Revolution?

It was Lenin and his socialist ideology that gave action to the discontent amongst the really terrible suffering caused by engagement in WWI with inferior weapons and equipment and support for the military He was late on the scene, apparently, but in the late autumn it was his determination and drive that caused the Soviets to vote in favour of armed revolution.

The provisional government was overthrownin a planned revolution, whereas the March revolt was unplanned and therefore messier and less effective. Lenin's message of Peace, bread, land' was just what the beleaguered people needed.

He was the leader of the Bolsheviks and knew well how the people were sick of war, hunger and hardship - Howeer, it was the brilliance of the Red Guard led by Trotsky that secured the bloodless takeover.