Posh lefty handwringers/Champagne Socialists/The Islington mafia call them what you like, but I think they are unfairly maligned.
Because in purely self economic terms it would be more beneficial to adopt a right wing stance and advocate less taxation, cuts in stamp duty and inheritance tax, yet they take an opposing view in the interests of fairness and justice.
By contrast, Middle/upper class Tories act largely in their own interest.