Prestige of a Communist revolutionary in Connecticut (6)
I believe the answer is:
'prestige' is the definition.
'a communist revolutionary in connecticut' is the wordplay.
'communist revolutionary' becomes 'Che' (Che Guevara).
'in' means one lot of letters goes inside another.
'connecticut' becomes 'CT' (US postal abbreviation).
'ache' going within 'ct' is 'CACHET'.
'of' acts as a link.
(Other definitions for cachet that I've seen before include "Distinctive stamp" , "Official seal - prestige" , "Prestige - seal of approval" , "Seal; mark of prestige" , "Feature or quality conferring prestige" .)