Sub Macro()

Dim oRng As range
Set oRng = ActiveDocument.StoryRanges(1)
    oRng.Find.ClearFormatting
    With oRng.Find.Font
        .Superscript = True
    End With
    oRng.Find.Replacement.ClearFormatting
    With oRng.Find.Replacement.Font
        .Superscript = False
    End With
     oRng.Find.Execute Replace:=wdReplaceAll
set oRng = Nothing
End Sub