Best drunk enters Spain twice (5)
I believe the answer is:
elite
'best' is the definition.
(elite can mean the very best of a group)
'drunk enters spain twice' is the wordplay.
'spain twice' means two replacements for 'spain'.
'drunk' becomes 'lit' (I've seen this in another clue).
'enters' is an insertion indicator.
'spain' becomes 'e' (abbreviation for Espana).
'spain' becomes 'e' (abbreviation for Espana).
'e'+'e'='ee'
'lit' put within 'ee' is 'ELITE'.
(Other definitions for elite that I've seen before include "Choice; best" , "twelve pitch in the office" , "Select body, cream" , "Letter size; superior group" , "High society" .)