Appeal of Daily Mail, initially (5)
I believe the answer is:
charm
'appeal' is the definition.
(synonyms)
'daily mail initially' is the wordplay.
'daily' becomes 'char' (both can mean a cleaner).
'initially' indicates taking the first letters.
The first letter of 'mail' is 'm'.
'char'+'m'='CHARM'
'of' acts as a link.
(Other definitions for charm that I've seen before include "small ornament" , "Engaging quality" , "Entrance, bewitch" , "Appeal; trinket" , "Something believed to bring good luck" .)