Seen from the perspective of power centers Clinton once had all the support she needed. But she then lost a decisive group due to her uncompromising neo-conned foreign policy. Here is an interesting take based on a theory from the 1950s:
[T]he power elite can be best described as a "triangle of power," linking the corporate, executive government, and military factions: "There is a political economy numerously linked with military order and decision. This triangle of power is now a structural fact, and it is the key to any understanding of the higher circles in America today."
The 2016 US election, like all other US elections, featured a gallery of pre-selected candidates that represented the three factions and their interests within the power elite. The 2016 US election, however, was vastly different from previous elections. As the election dragged on the power elite became bitterly divided, with the majority supporting Hilary Clinton, the candidate pre-selected by the political and corporate factions, while the military faction rallied around their choice of Donald Trump.