Evangelist spread cheaper religion primarily (8)
I believe the answer is:
preacher
'evangelist' is the definition.
(I've seen this before)
'spread cheaper religion primarily' is the wordplay.
'spread' indicates an anagram.
'primarily' says to take the initial letters.
The first letter of 'religion' is 'r'.
'cheaper' anagrammed gives 'preache'.
'preache'+'r'='PREACHER'
(Other definitions for preacher that I've seen before include "Sermoniser; minister" , "Someone spreading a gospel" , "Religious speaker" , "Religious minister" , "Minister, clergyman" .)