How Did Stalin Manage to Assume control over Russia in the Five years following the Death of Lenin in 1924?

How Did Stalin Manage to Assume control over Russia in the Five years following the Death of Lenin in 1924?
The death of the Russian leader, Lenin, in 1924, left Russia without a leader and the USSR seemed to be in a political vacuum. The most likely candidate to take Lenin’s place was Trotsky, a Communist leader who was well known and a good speaker. No one thought that Stalin was also quietly campaigning against Trotsky, though Lenin had warned the Party of him, before he had died.
As General secretary, Stalin could appoint whichever communists he wished to Party positions, so he used this to his advantage by appointing his supporters into the most powerful and important jobs in the Party. By being General Secretary, Stalin also insured that he would always be aware of any news to do with The Party. He used his post to expel supporters of Trotsky, who was also campaigning to be leader of the Communist Party. Because the job of General secretary was considered boring and not important by the Communists, no-one thought that Stalin was a threat to Trotsky.
