It seems increasingly likely that Hillary Clinton will win this election, perhaps carrying into the beginning of her term at least a slim Senate majority, though almost certainly still facing a Republican-dominated House. She could still lose it if there is some new last-minute very damaging revelation, but it would have to be very, very damaging indeed to have any effect, because the majority of the electorate seems to have already made up their minds. Trump meanwhile is self-destructing, unable to keep his cool and stay on message or resist responding over the top to provocations, and Hillary has learned to provoke him, as she did in the first debate.
Of course this general upset in the voting populace is just beginning. Hillary's election won't put an end to it by any means. The Trump Republicans will be furious, and will obstruct her at every turn, and the Bernie Sanders Democrats will be disappointed by her inaction on the issues they care about. Expect a disastrous 2019 mid-term election for the Democrats, who already face difficult demographics in that election (Democrats will defend 25 Senate seats to the the Republican's 8).
Hillary's major populist domestic policy proposals, thing like free college education for everyone and expanded Medicare and Medicaid eligibility, will go nowhere not only because the Republican House will obstruct them, but because there is no way to pay for them. Like Obamacare, they are fiscally unsustainable. Meanwhile she will face severe difficulties with Obamacare, which is collapsing and is still, to this day, unpopular with a majority of the electorate. And she may well face another mini-recession, just because they tend to come at 8-10 year intervals and we are overdue.
Internationally she will face a series of intractable issues - Brexit fallout, the general disarray in the EU, China's continuing aggressiveness in the South China sea, Russia's spoiler role in the Middle East and Eastern Europe, North Korea's continuing nuclear and missile advances, the endless Middle Eastern wars, and perhaps a new Israeli-Palestinian clash, which also comes in cycles and is overdue. These are all no-win situations for any president, however competent they are, so people will no doubt be disappointed however she responds.
That suggests that the next president, whoever she/he is, will likely be a one-term president, meaning that this whole election upset will repeat again after four years. If, as is likely, the Democrats take the White House, they will not feel the need to rethink their strategies and positions. The Republicans, on the other hand will have to look at this disastrous election and rethink a lot of things. It will be interesting to watch the internal Republican civil war and see how, in the end, they reshape the party.