Sociological polls and other sources, as well as electoral statistics, show that Soviet power in 1918-1989 met the main criteria for legitimacy. In 1918-1929, the majority of voters, and in 1931-1989 over 83% of the electorate, were loyal to the Soviet regime, trusted the communists and the general course and current policy, were satisfied with the status as ordinary builders of socialism, and believed in the socialist project. Official information on turnout and voting is trustworthy, although it has serious shortcomings and likely underestimates the scale of the protest vote (failure to appear, damage to ballots, voting against). Election results were influenced by electoral laws, propaganda, and control over the course of voting. However, clean elections have never happened anywhere. The legitimacy of power in any civilized country was supported by developed propaganda, and in the USSR it was not more powerful than, for example, in the USA or Germany. The study allows us to assume that until the mid-1980s the people's confidence in Soviet power was ensured not so much by propaganda as, first, by achievements of the USSR, which were considered by the majority of the population to be real, significant, and deserving of respect; second, by faith in the socialist project; and third, by peculiarities of political culture of the peasantry and the proletariat inherited from pre-revolutionary times. From their perspective, the people interacted with authorities and participated in management. The socialist project for only a small minority represented only a grandiose myth, a gigantic propaganda campaign, and an adventure or scam of world-historical scale.