The 90s were a constant Clinton sex scandal from the time he started running for office through his impeachment and people still talk about it. Simultaneously, there was the Harken energy scandal, featuring influence peddling by not-yet-President G.W. Bush. Etc.
Vox claims "the most important election ever" started in 2000 and has continued since, but I think that has more to do with when the author became politically aware than anything else.
https://www.vox.com/21504729/most-important-election-bush-go...
Consider Johnson's TV spot from the 60s, tacitly telling Americans that the election was a contest between L.B.J. and nuclear apocalypse:
https://www.youtube.com/watch?v=riDypP1KfOU
I encourage anyone to look back further for more extreme elections.
The peaks of the unrest seem to happen near times when there's a shift in "Party System." We're currently in the US's Sixth (or is it Seventh?) Party System:
https://en.wikipedia.org/wiki/Sixth_Party_System#Campaign_fi...