David Cameron is under intense pressure to crush Ukip in next month’s Rochester by-election after senior figures in his own party blamed him for the Eurosceptic party’s surge. After losing the previously safe Tory seat of Clacton to Ukip, the battle in the seat of Rochester and Strood, Kent, has become a critical test of the Prime Minister’s authority, warned MPs. The Tories had been braced for defeat in Clacton where the Ukip candidate was Tory defector Douglas Carswell – a popular MP in the constituency. Nonetheless, there was alarm at the scale of his triumph. Scroll down for video
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David Cameron says he is prepared to throw 'everything we can' at election
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Lord Ashcroft said Cameron must take 'large part' of credit for rise of Ukip
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Trying to avoid second defeat to a Ukip defector after Douglas Carswell
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Mr Carswell became Ukip's first MP last night after victory in Clacton
After the result, former Tory deputy chairman and pollster Lord Ashcroft, a regular critic of Mr Cameron said scathingly: ‘The @placeholder leadership must take a large part of the credit for the rise of Ukip.’