"The reason is that nominating centrist Democrats who don't speak to class issues will result in a great swathe of voters simply not voting. Conversely, right-wing candidates who speak to class issues, but who do so by harnessing a false consciousness — i.e. blaming immigrants and minorities for capitalism's ills, rather than capitalists — will win those same voters who would have voted for a more class-conscious left candidate. Piketty calls this a "bifurcated" voting situation, meaning many voters will connect either with far-right xenophobic nationalists or left-egalitarian internationalists, but perhaps nothing in-between.
Piketty's paper is an inconvenient truth for the Democratic Party. The party's leaders see themselves as the left wing of capital — supporting social policies that liberal rich people can get behind, never daring to enact economic reforms that might step on rich donors' toes. Hence, the establishment seems intent on anointing the centrist Democrats of capital, who push liberal social policies and neoliberal economic policies."