The following comes from a March 15 Salon article by Patricia Miller:

It’s one of the central contradictions of American politics: that there’s no such thing as the “Catholic vote,” yet the Catholics vote still matters.

There’s no “Catholic vote” in terms of Catholics representing an electoral bloc that votes according to what their bishops tell them, or in lockstep with the tenets of their religion. Yet winning Catholic voters has been essential to almost every presidential victory in modern times. And the defection of Catholics voters has played a role in some of the most consequential congressional turnovers in recent history — from 1994 to 2014 — making Catholics the ultimate swing voters. And for Democrats, that could be bad news.

While Catholics have been swing voters since Richard Nixon’s second term, white Catholics are now identifying as Republican by historic margins. According to the most recent polling from the Pew Research Center, 53 percent of white Catholics now favor the GOP, versus 39 percent who favor the Democrats—the largest point spread in the history of the Pew poll. And for the first time, white Catholics are more Republican than the voting group usually considered the ultimate Republicans: white Protestants (a designation that includes both mainline and evangelical Protestants).

These are ominous signs for the Democrats, evincing a new and growing allegiance with the Republican Party that has long-term implications.

So why are white Catholics abandoning the Democratic Party? There are some long-term trends at play. Steve Krueger, head of the group Catholic Democrats, notes that conservative bishops have been beating the war drums since the George W. Bush administration, even going so far in some cases as to argue that “good” Catholics can’t vote for Democrats because of their support for abortion rights and, more recently, same-sex marriage — which has resulted in an increased politicization of the church.

Stephen Schneck of Catholic University’s Institute for Policy Research and Catholic Studies has noted that there’s been a certain “distillation” of the Catholic vote as a record number of presumably more liberal-leaning Catholics — some one-third of those raised Catholic — have left the faith altogether. “More and more of those who remain are those who actively choose to embrace the church and its teachings,” he wrote.

But neither of these trends explains why white Catholics have abandoned the Democratic Party so suddenly and so dramatically. After all, in 2008 Barack Obama managed to keep his margin of loss of white Catholic voters to John McCain to just 5 points. But four years later, he lost the white Catholic vote to Mitt Romney by a stunning 19 points.

Krueger points to the Catholic bishop’s demonization in 2011 of the “contraceptive mandate” in the Affordable Care Act, and their subsequent ginning up of the war on “religious liberty” — which was joined by elements of the religious right and fused with its war on Obamacare — as another factor helping to drive Catholics toward the GOP. And the numbers bear Krueger out. According to Pew, between 2009 and 2014, the number of white Catholics who said the Obama administration — and by inference the Democratic Party — was “unfriendly to religion” more than doubled from 17 percent to 36 percent.

“The shift in the Catholic vote should really be a wakeup call to the Democrats,” says Krueger. “White Catholics are 18 percent of the electorate and Catholics vote 1 to 2 percentage points above their representation in the overall population. This is a significant voting bloc that now perceives Republicans as being more welcoming to people of faith.”