Nigel Farage has conceded that Ukip contains “some idiots”, but maintained that media coverage of the controversies surrounding the party in the lead-up to the European elections has been “completely disproportionate”.
Speaking in Dover, Kent, at the launch of Ukip's new billboard campaign for the elections, Mr Farage said that he believed the party’s “simple” message would resonate with voters across the UK.
Distancing himself from the so-called “idiots”, the Ukip leader claimed he had “never heard” of a candidate who posted numerous tweets espousing extremist views.
And Mr Farage also defended the embattled Top Gear presenter Jeremy Clarkson over the n-word row, saying it was “just typical Clarkson”.
The Twitter account of Harry Perry, standing for Ukip in Offerton, is a stream of Islamophobic and homophobic abuse.
Mr Farage said: “I've never heard of the bloke until last night. I've no idea who he is.
"I think he comes from the north west of England. Clearly his attitude and views are entirely inconsistent with being a member of Ukip. Simple."
He added: "I could show you 14 elected councillors from the Lib Dem, Labour and Conservative parties who haven't just said nasty things, they've been convicted this year of nasty things.
“And yet it never makes a national headline. I am not saying we haven't had our problems, we have.
"Every party has these kinds of problems but there is a completely disproportionate media spotlight on what goes wrong in Ukip compared to the others."
Ukip gaffes and controversies
Ukip gaffes and controversies
1/12 Neil Hamilton
Picture Exclusive: The year is 1998. The venue is a Springbok Club meeting. The flag is a symbol for white supremacists in South Africa. And the speaker is Ukip’s deputy chairman, Neil Hamilton
2/12 Kerry Smith
Kerry Smith resigned as would-be MP for South Basildon and East Thurrock after it emerged he had mocked gay party members as “disgusting poofters”, joked about shooting people from Chigwell in a “peasant hunt” and referred to someone with a Chinese name as a “Chinky bird”
3/12 Natasha Bolter
Former Ukip member Natasha Bolter was suspected of not having the teaching qualifications she professed to, only days after it was revealed that claims of her having attended Oxford University were also false
4/12 Ukip Calypso song
Mike Reid released a single in praise of UKIP trying to control the UK's borders, only to withdraw the single after being accused of racism for singing in a Jamaican accent
5/12 Farage 'car-crash' interview
Ukip spin doctor forced to intervene as Farage falters in disastrous radio interview
6/12 Janice Atkinson
Janice Atkinson, Ukip's South East chair, pictured by protesters while campaigning in Ashford, Kent with local party chair Norman Taylor
7/12 Ukip cancels Freephone
Ukip cancels Freephone number after protesters repeatedly called to push up costs
8/12 Farage 'car-crash' interview
Mr Farage appeared to be caught out on a number of issues, from Romanian neighbours to people speaking foreign languages on the train
9/12 Ukip employs illegal immigrants
Ukip criticised after European election candidate found employing illegal immigrants
10/12 Magnus Nielsen
Ukip candidate: 'Take away the right to vote to improve election turnout'
11/12 London Live make-up
Ukip's Nigel Farage reportedly refused to go on London Live 'without professional make up-artist'
Nigel Farage says he is taking taking legal advice over “outrageous” allegations that he is responsible for more than £50,000 of “missing” EU funding that was paid directly into his personal bank account
Responding to Prime Minster David Cameron’s comments about not needing to discredit Ukip as they do a "good enough job themselves", Mr Farage laughed and said: "It was good clever politic. I'll give him that. Yeah, we've got some idiots.
“What is happening here is the establishment are singling out a handful of unpleasant comments made by Ukip people and yet the other parties do these things and say these things it would appear with impunity.
"The other thing Mr Cameron said is that I was a chicken.
“Well, I'll tell you what Dave, why don't you come on telly and do a debate with me?”
Ukip’s campaign poster features a picture of the White Cliffs of Dover with an escalator running up the middle and the slogan: “No border. No control. The EU has opened our borders to 4,000 people every week.”
The poster adds: “Take back control of our country.”
The Ukip leader believes his party's “simple” message about immigration will get the public, if not politicians, talking.
“I've been trying over the course of the last few weeks to have a national debate on this issue.
"They point blank refuse to engage with me. On Monday this billboard will be going up on hundreds of sites right across the United Kingdom, and even if the politicians don't want to discuss this issue, I think this very simple, straightforward message is going to get the public talking about it," he said.
He added: "We may well be on the edge of the biggest migratory wave yet to come to these shores and the British Government is impotent, there is nothing we can do.
“The only way to solve this Mr Cameron, and Mr Miliband, is for the British people to have a referendum so that we can discuss this openly and vote on it.”
Asked about the Clarkson row, Mr Farage said: “The more controversial Jeremy Clarkson is, the more people watch his programme, and the more money the BBC makes out of marketing a show that sells globally and makes them a fortune.
"I would think it's just typical Clarkson, getting very, very close to the line of being offensive but perhaps not quite going over it," he said.
Additional reporting by Press Association