Dear professor Wolff, do you agree with thinkers who thought and think that the right way for replacing capitalism is to first occupy the state (either evolutionarily or revolutionary), become the capitalist and then reorganize the production systems? It seems to me that when the state becomes the only capitalist around, then it may become reluctant to redistribute its wealth and power to the proletariate. Am I right in thinking so?
Yes, I think history supports your inference. That is not to deny that state capitalism might sometimes function as a way-station from private capitalism to a socialism or communism that did away with exploitation. Lenin hoped for just that process in early USSR history. However, consolidation of power in the state coupled with the pressures and consequences of a still-capitalist relationship within state enterprises can block the transition beyond state capitalism. A fully elaborated and documented argument about how and why that happened in the USSR can be found in the following book which would, I think, interest you a great deal:
S. Resnick and R. Wolff, Class Theory and History: Capitalism and Communism in the USSR, New York and London: Routledge Publicshers, 2002.