U.S. Sen. Bernie Sanders, an independent populist who may challenge Hillary Clinton for the Democratic presidential nomination, said Tuesday in Las Vegas that if he runs it will be to take on “the billionaire class” that’s getting richer while America’s middle class is in decline, with more people living in poverty. “Not only are we not winning the fight, we are losing the fight,” the Vermont senator said in a fist-pumping speech at a packed Culinary Local 226 union hall where workers cheered him on.