The problem for Trump in 2020 was twofold. First, turnout was up substantially over 2016, particularly among groups that opposed his candidacy. Second, the correlation between the density of White Christians and Trump support actually dropped since 2016. While more White Christians meant more support for Trump, that wasn’t as true last year as it was when Trump was first elected. In most counties, the margin for Trump shifted downward, even in many densely White Christian ones.