The traditional gender gap is losing ground as a key factor in politics to intragender gaps that have emerged among Republican and Democratic voters along the fault lines of masculinity and femininity. This recent development involves differences within each gender, as opposed to the gender gap between men and women, which came to the forefront in the aftermath of the 1980 election between Ronald Reagan and Jimmy Carter, Men — specifically white men — who see themselves as extremely masculine tend to support President Trump, while those who are weaker in their assessment of their masculinity — or in how...