Prime Minister Rishi Sunak has suffered another pre-election blow, after a top polling expert warned the Conservatives that their chances of winning stand at just 1 per cent. Sir John Curtice made the revelation during a speech at the University of Strathclyde in Glasgow, where the polling guru said there is a “99 per cent chance of Labour winning the next election”. Curtice argued that there is “clearly a very small chance that the Tories are going to be in Government after the autumn”, telling the crowd: “Are you surprised?” The Conservatives have sunk to their lowest poll rating since forme…