Hours before he took the podium, whatever President Barack Obama said Tuesday night was getting eclipsed on the Hill by all the excited chatter about the next person likely to speak before a joint meeting of Congress.

Expectations are growing that Pope Francis will be ascending the House rostrum this fall, becoming the first pontiff ever to visit the Capitol and the most important voice of worldwide moral authority to address lawmakers in person since Nelson Mandela two decades ago.

If the congressional appearance comes off, the pope would be guaranteed more than an enormous American television audience — likely surpassing the numbers that tuned in for this year’s State of the Union address. More importantly, Francis would gain a unique opportunity to present his ideas for a more socially just society while making direct eye contact with one of the world’s most influential groups. For all its partisan dysfunction, Congress has an unequaled capacity to either impede or manifest the papal vision with the legislative proposals it chooses to rebuff or enact.

The pope has already committed to being in Philadelphia the last weekend of September for a global conference on Roman Catholic family values. Vatican officials have signaled strongly in recent days that Francis’ first papal trip to the United States would begin the previous week, with stops in Washington as well as New York, and that a final itinerary would be announced at the end of February.

The likeliest date is Sept. 24, the day after Yom Kippur, even though the House is scheduled to be in recess surrounding the Jewish High Holy Day. (The Senate plans to be in session except on Sept. 23.)

Still, there’s no doubt the House chamber would be filled to overflowing. Most politicians are unambiguously eager to bask in the reflective glow of an international celebrity, and the opportunity to be seen listening to the first Latin-American pope would prove irresistible to lawmakers wanting to solidify their appeal to the burgeoning Hispanic population. Beyond that, the Holy Father would be a big draw because he’s the spiritual leader for more members of Congress than anyone else.

Catholicism has been the plurality religion in both the House and Senate for more than half a century. And the number of Catholics in Congress has been on the increase: They accounted for about 20 percent of all lawmakers in the 1960s and early 1970s, but their ranks have grown steadily to just above 30 percent now. That includes three of every eight freshmen and four of the nine top leaders: Speaker John A. Boehner, Minority Leader Nancy Pelosi and Majority Whip Steve Scalise in the House, and Minority Whip Richard J. Durbin in the Senate. (Like the pope, the House chaplain, the Rev. Patrick J. Conroy, is a Jesuit.)

Francis has had a standing offer to address Congress since March, when a formal invitation was delivered bearing the signatures of Boehner and Pelosi. At first blush, it appeared to be one of the rare instances when they sounded like they were singing from the same philosophical hymnal. But a closer reading of their statements reveals how each was seeking to apply a different political tone to the meaning of this relatively new papacy.

The pope’s calls for protecting “the ailing, the disadvantaged, the unemployed, the impoverished, the unborn” along with his championing of “human dignity, freedom and social justice,” Boehner wrote, “are among the fundamentals of the American Idea. And though our nation sometimes fails to live up to these principles, at our best we give them new life as we seek the common good.”

“Many in the United States believe these principles are undermined by ‘crony capitalism’ and the ongoing centralization of political power in the institutions of our federal government,” the Ohio Republican continued. “They have embraced Pope Francis’ reminder that we cannot meet our responsibility to the poor with a welfare mentality based on business calculations. We can meet it only with personal charity on the one hand and sound, inclusive policies on the other.”

Boehner’s conservative message was offset by Pelosi. The California Democrat hailed the pope as someone who “has lived his values and upheld his promise to be a moral force, to protect the poor and the needy, to serve as a champion of the less fortunate and to promote love and understanding among faiths and nations.”

There’s no guarantee, of course, that Francis would seek to define social justice for this particular polarized audience. An alternative might be to reprise themes from his bluntly critical annual message in December to the political organization he knows best. That would be the Curia, the team of administrators who run the Holy See while engaged in legendary bouts of barely secretive infighting.

Francis cataloged 15 “ailments and temptations” weakening their service — several of which might readily be diagnosed in members of Congress.

First on his list was the “disease of feeling immortal or indispensable,” a “pathology of power” that could entice the priestly bureaucrats into believing “they are superior to others and not here for the service to others.”

The pope also described diseases of “excessive planning and functionalism,” vainglory, rivalry and “bad coordination,” all of which he said come into view when one faction becomes obsessed with avoiding collaboration with another.

The final affliction he identified? It is, he said, “a disease of people who seek tirelessly to multiply power only aimed at calumny, and to defame and discredit others.”

Related:

Pope Francis Hints at U.S. Visit, Address to Congress

Boehner Invites Pope Francis to Address Congress

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