All I know is that Harry Potter is a lock. There are other likely contenders, but nothing nearly as much a lock as Potter. That is why 69 out of 71 of us voted for it.
The worst performing Potter film, Prisoner of Azkaban, made $249 million-- this one could do $25 million less than that and still comfortably make the top 5.
--Jason "the average Potter film makes $282 million" Evans