Unboundedly delighted by margins of election result (6)

I believe the answer is:

happen

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'result' is the definition.
(thesaurus)

I don't understand the remainder of the clue.

(Other definitions for happen that I've seen before include "Occur" , "Chance" , "perhaps for Yorkshire" , "Turn out" , "maybe, in the Yorkshire Dales" .)

I've seen this clue in The Hindu.

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