In many ways, Donald Trump is unique in American politics, but as I've mentioned before, I think he has some parallels with Ross Perot. Below the presidential level, I wondered about Jesse Ventura, who was elected governor of Minnestota as an independent in 1998. Ventura had more political experience than Trump--he'd served one term as mayor of a city of about 85,000. He also apparently had libertarian leanings, while Trump has mostly been a standard conservative since being nominated. Still, it seems that for both of them, a basic part of their image was that they were outsiders who would apply toughness and common sense.
Minnesota has a state poll, sponsored by the Minneapolis Star Tribune, that goes back many years. I combined results from two asked in the second half of October 1998 to get breakdowns by education and gender:
High school or less 30%
Some College 34%
College Graduate 20%
The differences by education and gender are similar to those found with Trump today.
Some contemporary analyses hold that the big difference by education in support for Trump and Clinton reflects long-term economic change--less educated people, especially men, are losing out from globalization. I don't know about Minnesota in particular, but the economic situation in the late 1990s was generally regarded as good, so the example of Ventura counts against this analysis. An alternative is that less educated people (maybe especially less educated men) are more attracted to tough-talking outsiders and less likely to be bothered by "gaffes" or outrageous statements. That would suggest that large educational and gender gaps are specific to this election rather than a sign of things to come.
[Data from the Roper Center for Public Opinion Research]