2000 or 1988

[Human]

I think 1988 is the most apt comparison.

Bush Sr was unlikeable/uninspiring/uncharismatic. Reagan was the incumbent president who was inspiring, charismatic, and adored by many. IIRC, Bush Sr had very low approval ratings and could've easily been defeated if he had a good opponent. Dukakis ran a terrible campaign. Bush Sr crushed Dukakis because he ran a terrible campaign and also because of Reagan's popularity. However, Bsuh Sr lost reelection in a landslide due to a weak economy, party fatigue, and a great opponent.

Likewise, Hillary is unlikeable/uninspiring/uncharismatic. Obama is the incumbent president who is inspiring, charismatic, and adored by many. Hillary has very low approval ratings and could've easily been defeated if the GOP had nominated a good opponent. However, Donald Trump is running a terrible campaign. Hillary will probably crush Donald Trump because he is running a terrible campaign. I predict that Hillary will only be a one term president due to party fatigue (people are going to get tired of Democratic Party control after 12 years).

If Donald Trump wins (which is very unlikely), then 1976 is an apt comparison.

Jimmy Carter was an anti-establishment outsider. He ran as an anti-establishment maverick and Washington outsider. The Democratic Party establishment hated Jimmy Carter. The Democratic Party establishment tried to do everything they could in order to stop him from winning the nomination. A movement arise from in the Democratic Party called ABC (Anybody but Carter). Plenty of Democratic Party politicians like Ted Kennedy refused to endorse Carter after he had won the nomination. The Democrats implemented a super delegate system after 1976 to make sure that candidates like Carter could never win. On the Republican side, Gerald Ford started out as the favorite. Ronald Reagan decided to run. He started a conservative revolution. His message of true conservatism inspired many across the nation. Reagan started a political revolution. He narrowly lost the primary to Ford. Carter relentlessly attacked his opponent for being a corrupt insider. He marketed himself as an anti-establishment outsider populist who'll bring change to Washington. Carter narrowly won.

Likewise, Donald Trump is an anti-establishment outsider. He ran as an anti-establishment maverick and Washington outsider. The Republican establishment hates Donald Trump. The GOP establishment tried to do everything they could in order to defeat Donald Trump. A movement arised called #NeverTrump. Plenty of Republican Party politicians like Jeb Bush refused to endorse Donald Trump after he had won the nomination. On the Democratic side, Hillary Clinton started out as the favorite. Bernie Sanders decided to run. He started a progressive revolution. His message of true progressivism inspired many across the nation. He narrowly lost the primary to Clinton. Donald Trump has been relentlessly attacking Hillary for being a corrupt insider. Donald Trump has been marketing himself as an anti-establishment populist outsider who'll bring change to Washington.