Four years ago, white evangelicals rallied behind Donald Trump's presidential candidacy, and he reveled in their adulation.
"The evangelicals love me, and I love them," Trump said repeatedly on the campaign trail. In his acceptance speech at the Republican National Convention, evangelicals were the only faith group he singled out for thanks, saying their support was "a big reason for me being here tonight."
In the general election, however, it was not the evangelicals who carried Trump to victory but Catholics, a group he had rarely mentioned in his speeches.
"People were quite amazed at the overall impact that the white evangelicals had in the election, but I think what was missed was the critical role of the Catholic voters," says Mark Rozell, dean of the Schar School of Policy and Government at George Mason University.
Despite losing the popular vote, Trump reached the presidency in large part because he won traditionally Democratic Pennsylvania, Michigan and Wisconsin, all states in which Catholics outnumber evangelicals by significant margins.
"It was the Catholic vote that won those states for Donald Trump," says Tim Huelskamp, a former Republican congressman from Kansas now serving as an adviser to the Catholics for Trump movement, a coalition that did not formally exist in 2016.
"There was less recognition four years ago," Huelskamp says. "I think the campaign [now] understands that. Sometimes the White House official side did not."
While still recognizing the overwhelming support white evangelicals continue to give him, Trump this year has paid far more attention to Catholics than he did four years ago.
Speaking last month at the National Catholic Prayer Breakfast, an event dominated by conservative Catholic lay leaders, Trump was full of praise for the denomination.
"I grew up next to a Catholic church in Queens, New York, and I saw how much incredible work the Catholic Church did for our community," he said. "These are amazing people."
White evangelicals and conservative Catholics have similar positions on many issues, sharing a strong opposition to abortion and LGBTQ rights and both advocating religious liberty. The Trump administration has emphasized its support for those views in its appeals to Catholic voters.
"The administration has made a concerted effort to reach out to Catholics in a way that we haven't seen in the past," says Brian Burch, president of CatholicVote.Org, a conservative group that was formed in 2005 but has become far more active in recent months.
"We've grown every year," Burch says, "but this year we grew exponentially."
The organization did not endorse a candidate in the 2016 presidential election. This year, even with a Catholic candidate on the Democratic side, the group is wholeheartedly supporting Trump, with a $9.5 million campaign targeting Catholic swing voters in battleground states and featuring highly partisan television ads.
Among the claims in an ad running in Pennsylvania and Michigan is that "Joe Biden would force American Catholics to pay for abortions, sacrificing his Catholic values, to kneel before the leftist mobs."
The overall Catholic vote split almost evenly between Hillary Clinton and Trump in 2016, and a recent Pew Research Center poll shows Trump running behind Biden among Catholic voters this year.
The push to rally Catholic support for Trump, however, is highly focused on the more conservative Catholics who attend Mass regularly and follow church teachings closely.
"I think the campaign is distinguishing Catholics who support the church's position on life, the church's position on religious freedom and on school choice, and trying to turn that particular vote out," Huelskamp says.
The effort largely ignores less traditional Catholics.
"The more often you attend church, the more likely you are to vote for Donald Trump," Burch says. "The less likely you are to practice religion, the more likely you are to vote for Joe Biden. Regular church attendees are a decisive voting bloc, and turnout among those Catholics in particular is the area that we are focused on."
It's a targeted outreach strategy that is well supported by research. Rozell, who has studied the Catholic vote for many years, says it is no longer as monolithic as it was when U.S. Catholics rallied behind the candidacy of John F. Kennedy.
"It's religious practice, not religious identity, that really is the cue to how Catholic voters vote," Rozell says. "Among those Catholics who regularly attend religious services, they tend to be more conservative politically [and] vote Republican. Those who attend religious services infrequently or not at all tend to be much more heavily Democratic."
A recent NBC/Marist poll of likely voters in Pennsylvania, where white Catholics make up about a quarter of the electorate, found that practicing white Catholics favored Trump by more than 40 points, while those who call themselves nonpracticing supported Biden by about 25 points.
Given such findings, Trump's campaign now sees that it's conservative Catholics, not white evangelicals, who hold the key to his reelection, at least in the hotly contested battleground states.
For the Trump campaign, the effort to single out conservative Catholics is made much easier because they are heavily concentrated in particular media organizations, charitable foundations and advocacy groups.
"Where conservative Catholics have the edge on more progressive Catholics is that they have set up networks and institutions that allow them to get together," says Cathleen Kaveny, a theologian and legal scholar at Boston College who writes often on Catholic issues. "My impression is that they've got quite a lot of money. Liberal Catholics tend not to have that amount of money."
Among those institutions are CatholicVote.Org, the National Catholic Prayer Breakfast and the Catholic League. Conservative Catholic media organizations include EWTN News, the National Catholic Register and Church Militant. Together, such institutions constitute a Catholic right wing.
"Key parts of it are very narrow, very elite and very substantial," says John Carr, director of the Initiative on Catholic Social Thought and Public Life at Georgetown University.
Carr worked for 20 years at the U.S. Conference of Catholic Bishops, long the main policy and advocacy arm of the U.S. Catholic Church. The conference cannot endorse political candidates, however, and it has been careful not to engage too aggressively in political debates. Conservative Catholic leaders are now bypassing such traditional church power centers.
"What is relatively new is they have established parallel institutions, unconnected to the overarching institutions," Carr says.
Those institutions and the media organizations associated with them now provide an entree into the conservative Catholic world, thus enabling targeted outreach to a constituency that is key to Trump's reelection.
