The difficulty for Farage is that while many voters approve of Ukip's immigration policies, there are many more for whom Ukip's reputation as a racist and nasty party remains a major turn - off.
They think they risk turning what they remain convinced could be an «electoral game - changer,» as one aide to David Cameron called it, into a millstone if they get the language too strident and play into the old Tory image of «the nastyparty.»