Nigel Farage, the leader of Ukip, has hit out at the wrong sort of people which his party has attracted, promising to "professionalise" it and not tolerate any embarrassment.
Mr Farage told The Times that in the past Ukip had "got it wrong" with people who turned out to be "disappointments".
He said: "It's very natural that a newish party will attract all sorts of people," adding that Ukip had not always been successful 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".
Mr Farage said he wanted the party to become more professional and admitted that in its early days Ukip had a "struggle with talent".
He said he wanted the party to have a "disciplined election machine", and also hinted that candidates would have to curb any eccentric views, saying: "We must together be campaigning on similar issues."
The party will hold day-long assessment centres to find the best candidates to put forward for next year's general election, The Times said.
Mr Farage told the newspaper it was "not just about the odd barmy opinion - it's really to try and work out whether these are reliable, steady, solid people."
Ukip faced embarrassment this month when a local councillor, David Silvester, said the recent floods had been God's punishment for new gay marriage laws.
It also emerged yesterday that one of its members, MEP Godfrey Bloom, mocked a disabled student during an Oxford Union debate last week, asking whether he was Richard III, the medieval king who suffered a spine deformity.
Looking ahead to the elections, Mr Farage claimed that a third of Ukip's support now came from former Labour voters.
But he risked alienating this new campaigning ground by defending large bonuses for bankers, saying: "The very thought that the bureaucrats in Brussels now set the limits we can pay the highest earning people in London is truly astonishing."
But he attacked the pay of some in local government and non-governmental organisations, saying it was a bigger issue than the pay of bankers.