Why did Stalin Win the Struggle for Power, 1924-1929?

In 1922 the leader of the Communist Party in the Soviet Union (CPSU), Vladimir Lenin, appointed Joseph Stalin as the General Secretary of the CPSU, which was a job that at the time no person with power wanted, so a not so well-known Georgian was given the position. In that same year, Lenin suffered a stroke and began a long physical and mental break down, in which the powerful Communist even started to have doubts about the things that he and his party stood for.
Stalin had in fact been given a position that he very cleverly manipulated to increase his chances of achieving his aim, which was to be the successor to Lenin as the leader of the CPSU. …