Reform winning the next election is growing more likely because the party's backers are driven by ideology rather than protest, the UK's leading pollster said yesterday.Professor Sir John Curtice said his latest analysis was that the insurgent party's supporters are a 'coalition' of people with 'distinct socially Conservative views'.It means turning around the state of the sluggish economy or improving the NHS 'might help' Labour but is 'unlikely to be sufficient' to stop Reform's momentum.While he predicted the party's popularity is unlikely to surge much above 30 percentage points, he said this could be 'a potentially winning number' at the next election because UK politics is so fragmented and would still represent as much as a nine or ten point leader over Labour or the Tories.He also said Reform has been eating the Tories for 'breakfast, lunch and dinner' in terms of peeling off Right-leaning voters.Reform is hovering around 26 to 27 percentage points, Labour 17 to 19 and the Tories 18 to 19 in current polls.It came as the veteran pollster launched the latest British Social Attitudes (BSA) survey, which has studied whether support for Nigel Farage's insurgent party is just a 'protest vote' or whether its growth is based on firmer foundations which could last.It comes after Reform won 1,450 council seats at last month's local elections, including hundreds in Labour's traditional heartlands in the Midlands and North.