Pope Francis arrives in the United States on Tuesday amid raging partisan debates in Congress over abortion, immigration and climate change, giving him an extraordinary platform from which to influence — and roil — lawmakers of both parties.
The politics of the pope's visit, which includes a meeting with President Barack Obama at the White House, a speech before the U.N. General Assembly, and a first-ever papal address to Congress, will be further complicated by a presidential election in which matters of faith have featured prominently, and sharp lines have already been drawn over the Vatican's recent softer tone.
The leader of the world's 1.2 billion Catholics generally speaks on broad principles drawn from Church teachings — helping the poor, elevating human life — rather than making policy prescriptions. But Pope Francis, riding a wave of popularity that rivals that of Pope John Paul II, has shown an ability to speak more directly on sensitive political issues.
"He could make both sides of the aisle squirm a little," said Frederick C. Bauerschmidt, a theology professor at Loyola University Maryland. "Pope Francis has shown himself willing to get specific."
His two-year-old papacy has been defined so far by a change in tenor, not doctrine, watchers say. He sent shock waves through the church by responding in 2013 to a question about gay priests by asking, "Who am I to judge?" He has also been vocal on immigration, calling last year's surge of Central American children into the United States a "humanitarian emergency."
Nearly 60 percent of Americans have a favorable view of the pope, according to Gallup — significantly higher than Obama and Congress.
The pope is scheduled to speak to a joint session of Congress on Thursday as lawmakers are grappling with a debate over government funding that is tied to abortion. Some Republicans are threatening to block legislation to fund the government beginning Oct. 1 unless money for Planned Parenthood is cut.
The organization, which performs abortions, receives federal funding to provide other medical services, such as cancer screenings.
The Catholic Church has for centuries considered abortion a moral evil. The U.S. Conference of Catholic Bishops has lobbied heavily against a provision tied to Obama's health care law that required religious employers to offer insurance coverage for contraception.
At the same time, Pope Francis used a 184-page encyclical in June to blame humans for climate change, a move that gave Democrats cheer and put some conservative Republicans on the defensive. At least one of them, Rep. Paul Gosar of Arizona, has said he will skip the pope's speech Thursday in protest.
Nearly a third of Congress is Catholic, according to the Pew Research Center, and they're split evently between the parties: 81 Republicans and 83 Democrats. Despite the pope's rhetorical de-emphasis of church opposition to homosexuality and abortion, his critique of capitalism and his message on climate change, several Catholic Republicans — including House Speaker John Boehner — have said they are eager to hear him.
"The pope is going to talk about principles that I hope we all would share," said Rep. Andy Harris, a Baltimore County Republican and Catholic who met Pope Francis in Rome this year.
"We may disagree on how we get there, but I think the pope is going to talk to us about the importance of the discussion," Harris said. "His address will make us all, hopefully, think about the issues."
Democratic Rep. John Delaney, a Montgomery County Democrat and a parishioner at the Little Flower Catholic Church in Bethesda, declined an interview to discuss the politics surrounding the pope's visit. Instead, Delaney issued a statement calling the trip "bigger than politics."
Yet politics remain an unavoidable part of the equation. Republican presidential candidate Jeb Bush, for instance, was pressed on the pope's climate change encyclical in June. Bush, a convert to Catholicism, drew a line between his beliefs and his role as a leader.
"I don't get economic policy from my bishops or my cardinal or my pope," the former Florida governor said. "I think religion ought to be about making us better as people and less about things that end up getting in the political realm."
Critics pointed out that Bush told a religious organization in 2009, when Benedict XVI was pope, that "as a public leader, one's faith should guide you."
Seven candidates for president are Catholic. They include Martin O'Malley, who is seeking the Democratic nomination. The former Maryland governor published an op-ed in the National Catholic Reporter on Monday in which he tied Pope Francis' visit to the refugee crisis in Europe.
O'Malley, who is trailing in the polls to Hillary Clinton and Bernie Sanders, has been pressing the Obama administration to accept far more Syrian refugees. Clinton, the former secretary of state, echoed that sentiment in an interview over the weekend.
"How we respond to these and to so many other challenges — from education to health care — will speak to the type of country we are," O'Malley wrote. "It is not enough to reflect or have faith — we must have the courage to risk action on that faith."
Religion has also come up in the race for the Republican nomination. Dr. Ben Carson, a retired Johns Hopkins neurosurgeon, recently appeared to question the faith of front-runner Donald Trump. Carson, a Seventh-day Adventist, later apologized. Trump is a Presbyterian.
More recently, Carson drew criticism for saying he would not advocate the election of a Muslim to be president.
Whether Pope Francis' visit will influence any of the debates in Washington is unclear. While 90 percent of Catholics in the United States hold a favorable view of him, deep divisions remain about church doctrine.
A Pew Research Center survey this month found that 84 percent of Catholics say it is acceptable for unmarried parents who live together to raise children, for instance. Nearly four in 10 said homosexual behavior is not a sin.
"Our surveys find that U.S. Catholics disagree with a lot of church teachings, even though they have a very favorable view of Francis," said Jessica Hamar Martínez, a senior researcher at the center.
Even if the pope doesn't weigh into current political debates directly, the humble Argentinian is likely to have a broader message about capitalism and culture. And that might be difficult for members of both parties to listen to.
"He's going to come and praise the United States. But he's going to come and be very critical not simply of our politics, but of our culture. Can we hear that?" said the Rev. James Martin, editor-at-large of America magazine, a national Jesuit publication.
"He's not coming to support Hillary or Donald Trump. Or John Boehner or Nancy Pelosi," he added. "He's coming to preach the Gospel."
Baltimore Sun reporter Matthew Hay Brown contributed to this article.