Between 47 percent and 50 percent of Catholic voters supported Trump — a small decline from 2016, but enough to cost him the Rust Belt states that mattered most to his path to victory. Nationally, the president carried white Catholics by a 15-point margin, according to AP/VoteCast data, marking a significant decline from his 33-point margin of victory over Hillary Clinton four years ago.

Trump’s slippage with white evangelicals was less pronounced — surveys showed him carrying 76 percent to 78 percent of the white, born-again Christian vote — a slight decrease from 2016, when he won support from about 8 in 10 white evangelicals. But it had far-reaching implications for the president in states like Wisconsin, Pennsylvania and Georgia, where current vote totals show him losing by less than 1 percent.

The marginal decline in Trump’s appeal among Christian constituencies that overwhelmingly supported him against Clinton has led to finger-pointing inside his campaign. Some aides blamed the president’s inability to garner the same levels of support this cycle on his transactional view of religious voters, suggesting white evangelicals and Catholics in some parts of the country may have felt taken advantage of. Others accused the Trump campaign of becoming complacent in a race that saw unprecedented outreach by the Democratic nominee to evangelical and Catholic voters.