Bids by Conservative for supply of funds (7)
I believe the answer is:
coffers
'supply of funds' is the definition.
(I've seen this before)
'bids by conservative' is the wordplay.
'bids' becomes 'offers' ('offer' can be a synonym of 'bid').
'by' is a charade indicator (letters next to each other).
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'offers' put after 'c' is 'COFFERS'.
'for' acts as a link.
(Other definitions for coffers that I've seen before include "Supply of funds" , "Strongboxes" , "Treasury box" , "Treasury boxes" , "Financial reserves" .)