https://www.npr.org/sections/itsallpolitics/2013/12/06/248991810/how-two-similar-states-ended-up-worlds-apart-in-politics
Doug may have some thoughts as well.
Eugene McCarthy, Hubert Humphrey, Walter Mondale, Paul Wellstone, Keith Ellison, Ilhan Omar, Amy Klobuchar and Planned Parenthood's Senator Tina Smith, what makes you say Minnesota is liberal?
Why is Minnesota liberal? Or to put it another way, why do my neighbors lack political common sense?
Trump won 78 of Minnesota's 87 counties. Minnesota is a divided state that tips liberal. Things are changing in different directions in different demographics in the state as we speak, so the question is quite complicated. The divided legislature has flipped both ways recently, as has the Governor's office. Two suburban Republican congressional districts went Democrat this past year and one (and almost two) out-state Democratic district(s) went Republican. The politics of Minnesota is an unsettled question.
There are differences between Minnesota and Wisconsin but the tipping point may be that Minnesota's population is 3% more urban than Wisconsin:
https://www.icip.iastate.edu/tables/population/urban-pct-statesThe history of liberalism in Minnesota starts with a German and Scandinavian work ethic that made it possible to create generous safety net programs back when people had too much pride to accept assistance over work and only the truly needy would take it. The safety net now is defined as being up to 400% of the poverty line in healthcare while the wealthiest are in revolt over losing their own benefits with new limits on the state and local tax deduction. Rich people want government help too, and no one stops to question it.
The second and third generation wealth effect parallels the economic pattern of places of Sweden as well. Trade, innovation and hard work made great wealth possible. The next generations see the prosperity but not the importance of the conditions that created it. Outgoing Governor Mark Dayton is an example. His family of origin was neither Democrat nor liberal. He grew up in a famous and successful (Republican) family, went to Yale, married a Rockefeller and applied his own work ethic not to creating wealth but to the effort of giving back, in this case the selfless act of giving back other people's money.
Minnesota politics operates under the light of the liberal mainstream media effect. Without that bias over generations, Minnesota and the nation might have a balance closer to where Texas is today.
At some point Minnesota was lost to the Leftist takeover of the teachers unions and the schools. Local control of the schools lost out to a professional class of superintendents, administrators, curricula and an agenda of the Left that mostly didn't match the local interest. Same thing happened at the colleges. Liberal arts (small L) became Liberal arts and engineering and science too. Next they went after pre-K. Almost nothing is taught, printed or broadcast in Minnesota without a liberal, leftist agenda attached to it (exceptions below) and young people seem to have lost the question-authority attitude. With all that going in one direction, the state still is largely divided and worth fighting for.
How did all this happen? It happened in the same way that I credit my limited success in sports, weak opponents. Conservatives and independents in the '60s and '70s had no answer for the monopoly newspaper, nor for the networks and affiliates veering left. Conservatives watched the teachers union go far left and take over the schools and had no answer or counter to it. Republicans candidates adopted the positions of the Democrats to win elections while the Democrats turned further and further Left in policy while perfecting the soft words of compassion.
Republicans never united around the work of authors or concepts like George Gilder's 'Wealth and Poverty' where the policies of the Left are exposed for hurting the poor they are intended to help and building dependencies that people can't get out of. It wasn't the taxpayers who were hurt worst. When Ronald Reagan won over the nation with a more conservative vision, he won 49 states in reelection but not Walter Mondale's home state of Minnesota. Eventually Mondale would lose Minnesota to make it a perfect, historic 50, but now that seat in a divided state is in total control of the Left.
Like the nation, Minnesota has been mostly lacking in good conservative leaders and especially lacking in effective conservative messaging.
Conservative viewpoints are rare and harder to find than just opening the newspaper or turning on the news. Conservative outposts like powerlineblog.com are available but not (yet) mainstream. Public policy organizations like Center for the American Experiment research issues and tell the other side of the story but struggle to get their message out beyond those who are already in agreement.
For example:
https://www.americanexperiment.org/2018/05/new-data-shows-minnesotas-economic-growth-lagged-nation-2017/Where do we go from here?
As a wise man on this forum is known to say, the adventure continues.