Live presidentially, somewhat (6)
I believe the answer is:
reside
'live' is the definition.
(residing is a kind of living)
'presidentially somewhat' is the wordplay.
'somewhat' indicates a hidden word.
'RESIDE' can be found hidden inside 'presidentially'.
(Other definitions for reside that I've seen before include "Dwell - settle" , "Occupy a place" , "Inhabit" , "Live (in a place)" , "Make one's home permanently" .)