Interesting article and I'm sure the columnist is correct.
No one, including Mr Sanders, is talking about nationalising chunks of the US economy. Yet his policies are radical by American standards. He wants a single-payer healthcare system, along the lines of Canada, or the UK. He would abolish tuition fees for instate higher education. He would drive big money out of US politics, redistribute income, mandate paid holidays and increase social security benefits. He would also break up the “too big to fail” Wall Street banks. “Are we prepared to take on the enormous political and economic power of the billionaire class,” asks Mr Sanders, “or do we continue to slide into . . . oligarchy?”
... Mr Sanders raised $1.5m from small donors within 24 hours of his launch in early May. Although Mr Sanders is trailing far behind Mrs Clinton, his support exceeds that of almost any candidate in the Republican field. Is it a temporary protest vote? Or should Mrs Clinton’s donors start to worry?