Country lass pursuing senator with energy (7)
I believe the answer is:
senegal
'country' is the definition.
(I know that Senegal is a country)
'lass pursuing senator with energy' is the wordplay.
'lass' becomes 'gal' (both can mean a girl).
'pursuing' means one lot of letters go next to another.
'senator' becomes 'sen'.
'with' is a charade indicator (letters next to each other).
'energy' becomes 'e' (physics symbol as in E=mc2).
'sen'+'e'='sene'
'gal' put after 'sene' is 'SENEGAL'.
(Other definitions for senegal that I've seen before include "Northwest African country" , "Sea glen in the African state" , "Former French colony in Africa" , "Land" , "Part of Africa" .)