Chooses to run again arranging ad and poster (2-6)

I believe the answer is:

re-adopts

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'chooses to run again arranging' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'ad and poster' is the wordplay.
I cannot really understand how this works, but
'ad' is within the answer.
an anagram of 'poster' is 'reopts' which is present in the remaining letters.
No letters remain.
This explanation may well be incorrect...

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I've seen this clue in The Guardian.

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