Obama's model is indeed a form megalomania, indeed, but he employed the Nazi--not Bolshevik--formula in the 2008 election. The tactical comparisons to Hitler will better fit your suggestions: Leftwing Chickens Coming Home.
A mountain of stuff could be said here - but time does not allow me. I take your point about the 2008 election and coming to power through popular consent. Perhaps your view will prove out - I have always been hesitant to equate our prez with Stalin, and there is no perfect fit either way.
I do think you have over-simplified Stalin's rise to power. Lenin saw Stalin and his ambition, as well as his ?narcissism - perhaps thirst for power. He confided to those close to him that he was wary of Stalin [perhaps analogous to Bill Clintooon and the 'bamster.] Lenin died of declining health, and while there is NO historical evidence that Stalin had a hand in Lenin's death, I would not be shocked if such evidence should emerge.
Stalin did not assume Lenin's office directly; he took the position of Communist Party Secretary and manipulated that office into one of dictatorship... he would attack and replace Party officials - not as head of state but as Party leader.
None of this bears directly on my premise. My view is based on Stalin starting out as a narcissist - in my opinion - and then as he aquired power he became more and more addicted to it and wary of anyone who might threaten that power - viz: Trotsky... Kirov... most of the old Bolshevics... the babushka who swept the trash from Red Square... etc., etc.
For whatever reason, people came to adore Stalin - or avoid him, and the Cult of Personality was born. I see the Cult of Personality developing now - if you are in opposition your are seriously flawed and must be singled out from the populace. Meantime Stalin knew how to present himself as a lovable person - Pappa Joe - who only wanted what was best for the Union.
Well, there... now I have gone and dug a bit deeper despite time constraints. :^/