Force leader of Senate out of Congress? (5)
I believe the answer is:
exact
'force leader of senate' is the definition.
'exact' can be an answer for 'force' (I've seen this before). I'm not certain of the 'leader of senate' bit.
'out of congress?' is the wordplay.
'out of' becomes 'ex' ('out of' in Latin).
'congress?' becomes 'act' (I can't explain this - if you can you should believe this answer much more).
'ex'+'act'='EXACT'
(Other definitions for exact that I've seen before include "Not approximate, precise" , "Explicit" , "Absolutely accurate or correct" , "Call" , "without rounding" .)