Candidate on American brochure (10)
I believe the answer is:
prospectus
'brochure' is the definition.
(I've seen this before)
'candidate on american' is the wordplay.
'candidate' becomes 'prospect' (synonyms).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'american' becomes 'US' (abbreviation for United States).
'prospect'+'us'='PROSPECTUS'
(Other definitions for prospectus that I've seen before include "Brochure giving details of college courses etc" , "Promotional booklet" , "University entering opportunities for success in brochure" , "Booklet of what's on offer" , "Programme" .)