Politician turned up penniless in Welsh town (8)
I believe the answer is:
pembroke
'welsh town' is the definition.
(I've seen this before)
'politician turned up penniless' is the wordplay.
'politician' becomes 'mep' (Member of European Parliament).
'turned up' is a reversal indicator.
'penniless' becomes 'broke' (I've seen this before).
'mep' written backwards gives 'pem'.
'pem'+'broke'='PEMBROKE'
'in' is the link.
(Other definitions for pembroke that I've seen before include "An Ox., a Camb. college; Welsh town, castle" , "Oxford college; small table" , "Welsh port" , "Former Welsh county" , "Two Oxbridge colleges; a shire" .)