Staggered by socialist accepting slippery individual (6)
I believe the answer is:
reeled
'staggered' is the definition.
('reel' can be a synonym of 'stagger')
'socialist accepting slippery individual' is the wordplay.
'socialist' becomes 'red' (red is a kind of socialist).
'accepting' is an insertion indicator.
'slippery individual' becomes 'eel' (**).
'red' going around 'eel' is 'REELED'.
'by' acts as a link.
(Other definitions for reeled that I've seen before include "Staggered about in lively dance?" , "Staggered around as if drunk" , "Staggered or tottered" , "Lurched" , "Felt giddy, staggered" .)