The British National Party suffered a major setback in the local elections, losing six council seats.
Campaign group Hope Not Hate said the results left the BNP with just three councillors in England.
The BNP said all parties had suffered at the expense of Ed Miliband's resurgent Labour.
The far-right party's leader Nick Griffin said on Twitter: "Hammered by Labour - same as everyone. No surprise, no disgrace."
A message to activists on the party's website said: "How can Labour takes seats off us when Miliband is so unpopular? Is there something wrong with the British National Party or the public?
"The answer is that once the results are all in, Labour will be seen to have taken seats off everyone. And yet again, the plain truth is that this includes the BNP.
"Why? Because voters wanted to punish the LibDems and teach the Tories a lesson, and because - since nationalism's voter base is overwhelmingly working class, nationalist parties always do far better in elections when Labour is in power.
"When Labour is in opposition people unfortunately forget their misdeeds when in power."
Conservative Party co-chairwoman Baroness Warsi earlier linked the rise of the UK Independence Party (Ukip) with the decline of the BNP.
Lady Warsi appeared to suggest the number of candidates fielded by the eurosceptics had risen in line with a fall in the number standing for the BNP - a link with provoked Ukip's spokesman Gawain Towler to brand her "a bitch".
Mr Towler later apologised saying: "While her comments were contemptible, mine were out of order and I apologise fulsomely."