My husband's line has a John Mahn/Main/Maine/Maines!
The marriage record for him was in Sussex Co. NJ!The Zion Lutheran Church at Oldwick [now New Germantown].
You might look in that region of New Jersey. We are talking about the time period of 1785 for the marriage and they were likely there for some time previous.
We think the Mahn family came in at Philadelphia,before 1750 and were German by heritage.Our John's family went on to Canada after the Rev. War [took the wrong side, who knew!] and the Canadian census asks for ethnic heritage and they were always shown as German or Dutch[I suspect either they departed from Holland or someone shortened Deutsch to Dutch].