American can lie low, about to protect Republican (8)
I believe the answer is:
restroom
'american can' is the definition.
('can' is slang for toilet)
'lie low about to protect republican' is the wordplay.
'lie' becomes 'rest' (synonyms).
'low' becomes 'moo' (both can mean to make a cow noise).
'about' is a reversal indicator.
'to protect' is an insertion indicator.
'republican' becomes 'r' (abbreviation).
'moo' reversed gives 'oom'.
'rest'+'oom'='restoom'
'restoom' going around 'r' is 'RESTROOM'.
(Other definitions for restroom that I've seen before include "John" , "Where some may have recovered" .)