[quote=Gowi]
Even if we keep it as is: how would we go about explaining how theres like half-a-dozen magic superheroes in a city in ?
[/quote]

Magic, probably. Say they're just naturally more likely to arise there and/or are drawn subconsciously to the area. Maybe someone moved a magical artefact of silly power there,or its just naturally like that.
Though admittedly, Ireland or Tibet or Mesopotamia, bits of Greece or basically loads of places would be more appropriate than Maine ._.