As Marc Hetherington and I explained in our 2009 book, Authoritarianism and Polarization in American Politics, one of the key dynamics underlying the growing political chasm in the United States over the past generation has been the sorting of people with very different worldviews - anchored in polar personality types - into the two major political camps in America. As recently as 1992, when Bill Clinton first won the presidency, authoritarian-minded voters were about as likely to vote Democratic as they were to vote Republican. That is no longer the case. By 2004, white voters with an authoritarian bent had stampeded to the exits of the Democratic Party and joined the GOP. Conversely, the once large number of non-authoritarians who formerly supported Republicans had largely shifted their support to Team Blue. Those trends have only intensified since then, particularly in the age of Barack Obama. This development, the product in significant part of a decades-long shift in party appeals and changing demographics has fueled a bitterly acrimonious political divide characterized by fundamental and irreconcilable differences in worldview between the average Republican and the average Democrat. [my emphasis]I would want to look more closely at the empirical basis for this argument presumably cited in their book. If it's well-founded, that would be yet another reason for Democrats to stop worrying so much about trying to pitch their "bipartisanship" and the like.
Weiler argues that their findings shed light on the so-called "populist" aspect of Donald Trumps appeal in which he combines racist, xenophobic and militaristic appeals with more left-sounding criticisms of the economic elite:
... we also found that authoritarians were less reliably conservative on other key issues associated with the GOP. For example, the conservative economic agenda resonated less well with authoritarians than with other conservatives, quite consistent with how Trump is positioning himself. And though he's now pro-life, it's evident that Trump's newly minted views on that issue are half-hearted. As it happens, those scoring high in authoritarianism were themselves not especially distinguished in their support for the pro-life position. Those are two critical planks of the modern conservative platform and on neither are authoritarians particularly adamant, as a group.(There is probably no political concept which our Beltway Village press corps use more carelessly than "populism" - and that's saying a lot! I'm more inclined to use the concept in the sense of Ernesto Laclau. On Laclau, see, e.g., Dan Hancox, Why Ernesto Laclau is the intellectual figurehead for Syriza and Podemos The Guardian 02/09/2015 and the obituary for him by Spanish politician and theorist Íñigo Errejón: Ernesto Laclau, teórico de la hegemonía Academia.com 2014, Ernesto Laclau, theorist of hegemony Verso 04/30/2014.)
This observation of Weiler's sounds very plausible to me:
When pundits talk about the role of "white working class" support for the GOP, they are, to some degree, making an analytical mistake. As we showed in our analysis of the Clinton/Obama primary fight in 2008, in our book, as well as in analysis of election data from 2010 and 2012, what distinguishes Democratic from Republican voters among whites isn't education level or income level. It's authoritarianism. The data are consistent in this - low authoritarian white folks with less than a college education, or who earn less than the median income, overwhelmingly support Democrats. Conversely, whites with high incomes and high education levels but who also score high in authoritarianism strongly support Republicans. In other words, it's not "working-class whites" per se, who support very conservative candidates. It's authoritarians, whether they are working class or not. This, too, is consistent with the composition of the (not-so-mysterious) Trump coalition. [my emphasis]