Publication free of tax is a draw (6)
I believe the answer is:
magnet
'a draw' is the definition.
(I've seen this before)
'publication free of tax' is the wordplay.
'publication' becomes 'mag' (abbreviation for magazine).
'free of tax' becomes 'net' (eg net profit is profit after tax).
'mag'+'net'='MAGNET'
'is' acts as a link.
(Other definitions for magnet that I've seen before include "it could be a draw?" , "Focus of attraction" , "Lodestone, for example" , "Drawing influence?" , "Attractive type" .)