Rishi Sunak has been dealt a major blow after a pollster working in No10 quit and issued a chilling warning about the threat posed by Nigel Farage. Will Dry confirmed he resigned from Downing Street before Christmas and is now doing polling on behalf of the Conservative Britain Alliance who were behind the damning YouGov MRP poll. Dry, who campaigned to stop Brexit after voting to leave the European Union, released a stinging statement about Sunak’s premiership. He even warned Labour will be in power for at least a decade. In a statement given to The Sun, Dry said: “Everyone in this country ca…