They'll swear if Republican frames rogue (9)

I believe the answer is:

affirmers

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'they'll swear' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'if republican frames rogue' is the wordplay.
'republican' becomes 'R' (political abbreviation).
'rogue' indicates anagramming the letters (letters go rogue).
'if'+'r'+'frames'='ifrframes'
'ifrframes' with letters rearranged gives 'AFFIRMERS'.

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I've seen this clue in The Independent.

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