Supporters, lots getting hard facts (5,5)
I believe the answer is:
brass tacks
'hard facts' is the definition.
(I've seen this before)
'supporters lots getting' is the wordplay.
'supporters' becomes 'bras' (I've seen this in other clues).
'lots' becomes 'stacks' ('stack' can be a synonym of 'lot'**).
'getting' says to put letters next to each other.
'bras'+'stacks'='BRASS TACKS'
(Other definitions for brass tacks that I've seen before include "Basic facts (colloq.)" , "Hard facts" , "Basic realities (informal)" , "Real business" , "really mean business" .)