WASHINGTON — Pope Francis arrives in the United States on Tuesday as Congress is embroiled in raging debates 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 Obama at the White House, a speech before the United Nations General Assembly, and the first address by a pope to a joint session of 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 Roman 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 2-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 more than see Obama and Congress favorably.

The pope is scheduled to speak to Congress on Thursday as lawmakers debate government funding 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 the Affordable Care Act that required religious employers to offer insurance coverage for contraception.

At the same time, Pope Francis used an encyclical in June to blame humans for climate change, which cheered 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 in protest.

Republican presidential candidate Jeb Bush 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.”

CATHOLIC LAWMAKERS

Nearly a third of Congress is Catholic, according to the Pew Research Center, and they’re split evenly 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.

Seven candidates for president are Catholic. They include Martin O’Malley, who is seeking the Democratic nomination. The former Maryland governor wrote an op-ed in the National Catholic Reporter on Monday in which he tied 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.”

Ben Carson, a retired Johns Hopkins neurosurgeon and another presidential candidate, 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.

DEEP DIVISIONS OVER DOCTRINE

Whether 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 Martinez, a senior researcher at the center.

Even if the pope doesn’t weigh into current political debates directly, he 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 not coming to support Hillary or Donald Trump. Or John Boehner or Nancy Pelosi,” said the Rev. James Martin, editor-at-large of America magazine, a national Jesuit publication “He’s coming to preach the Gospel.”