As Americans are settling into the news that Donald Trump will be their next president, Hillary Clinton fans are processing a conundrum that political commentators simply didn't see coming: the biggest political upset in American history.
Where the polls predicted a modest, but meaningful lead for the Democratic candidate, something far different was happening in America's industrial heartland. And when it came to the polling booth, it showed.
So why did things go so wrong for Hillary Clinton? Here are eight key considerations:
1. The anti-establishment factor
From the moment the party primaries kicked off, to the moment Trump was announced as the 45th president of the United States, commentators and politicians alike recognised that this would be an election about the angry and the forgotten.
Dr Tom Long, a lecturer in politics and international relations at the University of Reading, sees the result in part as a continuing backlash against globalisation, and the desire to find an outsider to govern.
He said: "Obama's record has been very good in terms of the unemployment rate, but it's only very recently that the US has started to see improvements in wages. Wages have stagnated for a long time, particularly the bottom half of the income distribution. So some of these sorts of blue collar workers who formerly maybe had good-paying industrial jobs have been dislocated.
"Sanders appealed to that demographic by having a single-minded focus on inequality. Trump was able to tap into some of that too: if you just think of his slogan, "Make America Great Again", the "again" is backwards looking."
2. James Comey and the FBI email investigation
Clinton struck a controversial figure for her perceived lack of transparency. The double announcement that the FBI was investigating emails from Clinton's private server did little to hush claims from Trump that the former Secretary of State was "crooked", and should be "in jail".
FBI director James Comey, who announced less than two weeks before election night that the matter was being re-investigated, will have a lot to answer for in the eyes of Democrats, even though those investigations were dropped eight days later.
It was seen as a politically motivated move by some - something which would be well outside the remit of an FBI director - but whatever the forces driving the timing of the investigation, it will go down as a significant moment for Republican support.
America was happy to elect its first president of colour, but perhaps it still wasn't ready to see a female president at the helm.
Many saw this as a chance for America to prove that it was continuing the momentum of 2008 when Barack Obama's election hinted at a more equal society actually coming to fruition, but even with Hillary Clinton's experience as Secretary of State and significant support from women voters behind her, many others couldn't bring themselves to trust in her policies.
Commentators are now likely to focus on sexism as a key component of Clinton's downfall, even where dissolution with the establishment and Trump's strengths as a communicator are rival factors for his victory.
4. People don't like her
Of all the emerging trends throughout either presidential campaign, one kept up cropping up over and again: not many people liked either of the candidates.
Trump initially divided as many people within his party as outside it, but for voters Clinton seemed to represent more of the same, at a time when they wanted change. Numerous pitfalls along the way such as the disastrous FBI investigation into historical wrongdoing concerning her emails didn't help her public image, even after she was cleared.
At times socially awkward, at times dismissive of her opponent's abilities, Clinton was perhaps guilty of not listening enough to the forces of change. In the end the public simply didn't like her enough to see her through.
5. Millennials were voting elsewhere
Millennials - voters aged roughly 19 to 29 - were a key target for both camps in the run-up to the election.
They've tended to be a driving force for the centre ground of American politics, but this year the demographic took on a new momentum and started to turn to the same kinds of primary candidates that people in America's industrial heartland were paying attention to. That meant Bernie Sanders, and Donald Trump.
Tom Long said: "All of the early indications were that that group would go pretty heavily for Clinton, but might not turn out at the same rate that it turned out for Obama. And so part of that is probably a lack of real connection with Clinton - a lack of personal connection, and seeing her as part of the establishment and an establishment figure."
6. The polls
It happened with Brexit; it's happened in America. The polls simply couldn't predict that a man with no previous experience in government of any sort could become the leader of the most powerful nation on Earth.
If Hillary Clinton's camp were quietly confident as the country went to the polls on Tuesday evening, it was because all the predictions said she would win - if only marginally. That may well have contributed to her decision not to push hard for States like Wisconsin, which she did not visit - in stark contrast to Trump who visited some five times.
7. The swing states
Like all American elections, this one came down to the "swing states" - those that tend to flip between Republican and Democrat majorities from election to election. What commentators hadn't predicted, however, was that Trump could turn so many of them to his advantage.
Tom Long said: "Florida as always was really key, but the assumption of how key Florida was in part based on the thought that Clinton would win pretty solidly in northern states that have traditionally been democratic. And she didn't.
"Some of those battle grounds, which were very close, ended up being less key because Trump was able to flip the map in a way that I don't think the Clinton camp expected, and certainly most observers did not expect."
8. Donald Trump
At times startling, more often, bewildering. Clinton and many millions of people around her simply didn't see the potential that Donald Trump had until it was too late.
He made more headlines for controversy than he did for policy - although many of those proved to be pretty divisive too - but he tapped into something that the establishment figures never could: America's forgotten heartland, where people were tired of feeling let down by what they perceived to be "the system".
Love him or loathe him, Donald Trump has reminded us all that in America, really anything is possible.