Ukip has dismissed a poll suggesting that Nigel Farage will lose his attempt to become an MP, although party activists in Thanet South acknowledge that the fight to win the Kent seat is much closer and more volatile than previously thought.

The party has rejected the results of the survey, commissioned by Ukip's most generous current donor Arron Banks, as being rogue and based on weak methodology.

The ComRes poll of 1,003 people showed the Conservative candidate, Craig Mackinlay, a former Ukip activist, on 30%, Farage on 29% and Labour on 28%.