Anyone could be Women's President once, with one difference (7)
I believe the answer is:
whoever
'anyone' is the definition.
(I've seen this before)
'women's president once with one difference' is the wordplay.
I cannot really see how this works, but
'with' could be 'w' (abbreviation) and 'w' is found in the answer.
'one' could be 'o' (I've seen this in other clues) and 'o' is found in the answer.
The remaining letters 'hever' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'could be' is the link.
(Other definitions for whoever that I've seen before include "Anyone" , "Any or every person involved, doesn't matter" .)