Ukip won a council seat in South Tyneside last week. Norman Dennis was elected in Westoe ward with a majority of 51 over Labour.
The news will be a boost for the hard right party that is hoping to win its first MP in Clacton, Essex, on Thursday of this week. The by-election was triggered when Tory Douglas Carswell defected to Ukip last month. He is now standing in the seat for Ukip.
Ukip candidate John Bickley is also contesting a by-election in Heywood and Middleton, Greater Manchester, on the same day.
A group of anti-racist protesters targeted Ukip campaigners in Heywood and Middleton on Thursday of last week. And trade unionists, pensioners and students came to a Stand up to Ukip meeting in Clacton on the same day.
Activists also leafleted against Ukip in Clacton last Saturday.
Stand up to Ukip has called a national activist meeting on Sunday 9 November in central London.