From David Dayen in The New Republic here:
But The New York Times’s Neil Irwin might have found an answer [to the anger out there] last week, when he pointed to eye-opening new research from Princeton’s Alan Krueger and Harvard’s Lawrence Katz on Americans in alternative work arrangements, which they defined as “temporary help agency workers, on-call workers, contract workers, and independent contractors or freelancers.” This cohort of the workforce grew from 10.1 percent in 2005 to 15.8 percent at the end of 2015, representing an increase of 9.4 million workers. That’s all of the growth in the labor market over the past decade. ... “Angry” voters may simply be angry workers tossed into the Darwinian world of the modern economy, operating without any fallback support from their employers or their government. This was bound to find its way into our politics, but though solutions for these workers exist, nobody is talking about them.
At 8.2 million after 32 contests, the popular vote for Trump alone with 16 states yet to vote is set to surpass 12 million.