Financial supporter (10)
(Other definitions for benefactor that I've seen before include "Patron, sponsor" , "Donor to a good cause" , "One giving money to person/cause" , "Patronising sort" , "One provides bread" .)
(Other definitions for sponsor that I've seen before include "Promoter, godparent" , "Supporter or champion" , "surety" , "Patron or backer" , "One who backs" .)