The British National Party (BNP) came within 2,580 votes of winning a north Wales regional seat in the Welsh assembly election.
BNP leader Nick Griffin at the manifesto launch in Swansea
The far-right party won a record level of support on the regional lists, coming fifth in many cases.
In Wrexham, which has a large Polish community, the party won 9.4% of regional vote, and it secured more than 7% in Alyn and Deeside and Clwyd South.
The Commission for Racial Equality (CRE) called it "deeply disappointing".
The BNP also won more than 5% of the vote in Aberavon, Blaenau Gwent and Islwyn.
The party looked set to win nearly 5% of the vote across Wales, after putting up a record number of candidates in the election.
BNP leader Nick Griffin said the party had received more membership enquiries "than ever before" as a result of its campaign and predicted it was "just the beginning" for the party in Wales.
Mr Griffin said: "We've increased our vote massively on what we've done in the past and I'm sure that there will be reverses along the way.
"But, overall, our vote will carry on going up unless the other politicians start to listen to ordinary people and their concerns and take them seriously instead of giving them politically correct platitudes."
In the campaign, he described the number of migrants from Poland as the "main burning issue" in some areas of Wales and said a key priority was tackling a multi-cultural society.
The party's manifesto, called Putting People First, also called for the sacking of North Wales Police chief constable Richard Brunstrom.
The director of the CRE in Wales Chris Myant said he was concerned about the growing support for the BNP.
"It's deeply disappointing that a significant proportion of the electorate feel so alienated from democratic and responsible politics that they should turn to a party which is based on racism," he said.
"This is a warning to politicians across the spectrum that they have to address the feelings of social exclusion felt by many communities which have taken an economic and social battering.
"Racism is still a big problem in Wales and we need to demonstrate to local communities that diversity is not a threat and is not a danger and that politics based on prejudices simply don't deliver."
Independent Wrexham councillor Mark Prichard claimed BNP supporters had said "daft things" about migrants in the town.
He said: "I bumped into one of them in Wrexham town centre last week. I spent about 15 minutes chatting to him and the information he was giving out was incorrect.
"He told me that there was a large immigrant population of Poles, Romanians and Bulgarians and that they were 'taking our jobs' and if they carry on they will be 'taking over the town'.
"He was making statements saying the government was giving immigrants free cars, free telephones and £5,000 when they turn up to the job centre to register for work. Daft things really.
"It does scare me that the BNP are going round telling untruths. It upsets people.
"I just hope this is a protest vote because Labour is so unpopular, with Iraq, rural post offices being closed and the health service."
North Wales Race Equality Network chair Manu Patiar, said: "It's a worrying time for BME (black and minority ethnic) communities as well as for the oldest democracy in the world.
"The BNP are capitalising on the certain issues. Britain has had waves of immigration throughout its history, so how are these immigrants any different, especially as they are EU citizens?"