Nigel Farage has pledged to introduce a tough new vetting system to screen potential Ukip candidates, in a bid to strip out the more eccentric members of his party.
As he continued to distance himself from the comments of Ukip councillor David Silvester, who said extreme weather was the result of the same sex marriage bill, Farage promised to professionalise his party.
"It's very natural that a newish party will attract all sorts of people," he told the Times.
Ukip had not always succeeded in screening out the "Walter Mittys, seeking a role in politics which, in the end, they will let down not just us but themselves with".
Farage said he wanted a "disciplined election machine" which stripped out eccentric views and campaigns.
"We must together be campaigning on similar issues," he added.
"[It's] not just about the odd barmy opinion – it's really to try and work out whether these are reliable, steady, solid people".
It is unclear exactly how Farage intends to vet new recruits to the party.
Ukip already uses emotional and political cognition tests to screen potential candidates, but has continued to be rocked by eccentric and sometimes offensive outbursts from its candidates, MEPs and local councillors.
Writing in the Telegraph, the Ukip leader asked readers why the press always picked on his party.
"Headline after headline attacking either me or a silly comment by a UKIP councillor. But what doesn’t kill us will make us stronger," he said.
"Because the surging popularity of Ukip threatens the Westminster establishment, the voluntary side of our party is being subjected to the kind of scrutiny that no other political party has ever been put under.
"Whilst junior members of Ukip have their every word and faux-pas on Twitter and Facebook monitored, analysed and publicised, the three establishment parties are allowed to get away with much worse."
The pledge comes days after Farage branded the entirety of the Ukip 2010 manifesto "drivel".
The Ukip leader said he was not involved in drawing up the manifesto, which was written while we was preparing a bid for parliament.
But it later transpired that he co-wrote the forward to the document and spoke at its launch.
Among other measures, the manifesto proposed banning the burka in public buildings and forcing tax drivers to wear uniforms.
David Campbell Bannerman, who wrote the manifesto, but has now rejoined the Tory party, said Farage never believed in Ukip policy.
"I think Nigel is in terrible trouble over policies. He's never believed in them. He's on the ropes," he told BBC Radio 4's The World Tonight.
"We had 18 policy groups, very professional people. It was a very serious paper, but Nigel could not be bothered to read it, anything to do with policy. I'm afraid it's not good enough for someone who claims to be a serious political leader.
"You're dealing with someone who isn't bothered, isn't serious, is a bit of a joker, and it's not good enough. It's not a political party. It's a pressure group".