This may be a bit overboard; but is it possible that Victor Orena was one of the most powerful ''Acting Bosses'' of all time??
He was acting boss of the Colombo family which is basically a glorified street gang.
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I would personally pick Gerry Catena as the acting for Vito Genovese, a lot of people think that he actually became the official boss after Genovese died until sometime in the early 70s when he was in jail himself.
