Revitalise party that's winning (4)

I believe the answer is:

doup

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'revitalise party that's winning' is the definition.
I can't tell whether this defines the answer.

'party that's winning' is the wordplay.
'party' becomes 'do' (do can informally mean a party).
'that's winning' becomes 'up' (eg being up at half time in football).
'do'+'up'='DOUP'

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I've seen this clue in The Irish Times.

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