Invade on account of race (7)
I believe the answer is:
overrun
'invade' is the definition.
(overrunning is a kind of invading)
'on account of race' is the wordplay.
'on account of' becomes 'over'.
'race' becomes 'run' (run is a kind of race**).
'over'+'run'='OVERRUN'
(Other definitions for overrun that I've seen before include "Exceed time allowed - or conquer territory." , "Last longer than scheduled" , "Move too fast" , "last longer than planned" , "Stretch too far" .)