Pass on story about Democrat clash (7)
'clash' is the definition.
'pass on story about democrat' is the wordplay.
'pass' becomes 'col' (col is a term for a mountain pass).
'on' means one lot of letters go next to another.
'story' becomes 'lie' (story can mean a fabrication).
'about' indicates putting letters inside.
'democrat' becomes 'd'.
'lie' enclosing 'd' is 'lide'.
(Other definitions for collide that I've seen before include "Hit", "Smash together", "Run into", "Come into conflict", "Crash together".)