"Rather than using opinion polls as a basis on which to judge the wisdom of class politics, let’s take a rather different measure: general election results. In 1979, 1983, 1987 and 1992, Labour promised tax increases (but only for the wealthy) and got hammered. In 1997, 2001 and 2005, we pledged not to increase the basic or higher rates of tax. And golly! Look what happened!"
Ok, correlation and cause aren't necessarily the same thing. But there's a strong case that a class war strategy now – a retreat from the politics of aspiration – could mean a harsher political wilderness for Labour after the election.