Ms. Howard’s voting history and her views on immigration, welfare, and Obamacare suggest that she is a prime target for Mr. Trump and the sort of voter Mrs. Clinton would write off.

But here’s the thing: She has decided to vote for Hillary Clinton.

What matters here is not this one voter’s defection from party orthodoxy but what she wants from the next president and Congress. In some ways, she sounds eerily reminiscent of the Dayton housewife Richard Scammon and Ben Wattenberg highlighted in their 1970 book, “The Real Majority.” Then, the central character was the Dayton housewife and her concerns. Today, Jen Howard is no traditional housewife and her community, Aurora, Colo., is racially diverse. (Half the population is Hispanic, African-American, or Asian.) Yet her hopes and dreams, and in particular her fears, harken back to domestic strife and international uncertainty of 1970.

Last week I checked in with her again. Jen Howard knows whom she will vote against. Her view of Donald Trump: “He is acting like an idiot; he is crazy.” Her advice: “Shut up; be quiet.” Her only affinity with Mr. Trump is on immigration. And even here, she has many reservations about his position and considers “the wall” a ridiculous approach.