Party people's contribution (8)
I believe the answer is:
donation
'contribution' is the definition.
('donation' can be a synonym of 'contribution')
'party people's' is the wordplay.
'party' becomes 'do' (do is a kind of party).
'people' becomes 'nation'.
'do'+'nation'='DONATION'
(Other definitions for donation that I've seen before include "present" , "Money given to charity" , "An offering or charitable gift" , "Gift or contribution" , "Do anoint by way of a gift" .)