What Reasons Can you Give to Explain how Stalin Was Able to Seize Power in the USSR by 1928?

Stalin, Joseph Vissarionovich, 1879-1953, Soviet Communist leader and head of the USSR from the death of V. I. Lenin (1924) until his own death, b. Gori, Georgia. His real name was Dzhugashvili (also spelled Dzugashvili or Djugashvili); he adopted the name Stalin (man of steel) about 1913.
After the October Revolution of 1917, Stalin, already a member of the central committee since 1912 entered the Soviet cabinet as people's commissar for nationalities and began to emerge as a leader of the new regime. During the civil war from 1918 to 1920 he played an important administrative role on the military fronts and in the capital. He was elected (1922) general secretary of the central committee of the party, enabling him to control the rank-and-file members and to build an apparatus loyal to him.
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