Why did JFK lose Wisconsin to Nixon?

[mianfei]

Scandinavian Lutherans, even progressive ones, were leery of voting for Kennedy.  That’s also why Minnesota only barely went for JFK.

That is the key issue, and it must be remembered that Scandinavian-Americans were Adlai Stevenson’s strongest support group outside the South. The same was even more markedly true, of course, in the Pacific Northwest, which had been rapidly trending Democratic at state and local levels before 1960 and which a generic Democrat would likely have won at that election.