Are Americans listening? Pope Francis greets the crowd at the end of his weekly general audience on Dec. 3, 2014 at St Peter’s Square in Vatican. (Gabriel Bouys/AFP/Getty Images)

Pope Francis visits Washington, D.C. this week, where he will be the first pontiff to address a joint session of Congress. Since his election in 2013, Francis has attracted international headlines, been named Time Magazine’s Person of the Year, and left commentators speculating about a possible “Francis Effect” on the American Catholic Church.

Francis has a gift for shaping headlines, and his remarks to Congress are sure to be front-page news.

But how are average Catholic voters actually responding to some of the pope’s most prominent public statements? New research shows that Francis’s statements on religion in public life do matter to Catholic voters, particularly to those most likely to be found in the pews on any given Sunday.

Who is an American Catholic voter?

Francis will encounter an American Catholic community undergoing rapid demographic and political changes. While still a minority, American Catholics have come a long way from John F. Kennedy’s election, to say nothing of Al Smith’s failed 1928 run for the presidency, when anti-Catholicism played a prominent role on the campaign trail. Catholics serve with little controversy in positions of power in the executive, legislative and judicial branches.

The days of solid Catholic Democratic voting blocs are long in the past, with white Catholics becoming more conservative, Latino Catholics making up a larger share of the overall Catholic community, and lapsed Catholics contributing a significant portion of the politically progressive religious “nones.” This is no monolithic bloc, and its size and internal diversity make it a tempting target to partisans of various stripes. To paraphrase EJ Dionne, there is no Catholic vote, and it matters.

What is the pope talking about that has gotten people talking?

Francis has seized headlines in part because of what he has to say about religion’s role in public life — and how it marks a shift in the recent public priorities of many Catholic leaders. Shortly after his election to the papacy, Francis told a consortium of Jesuit media outlets that the church needed to find a “new balance” in public life rather than “obsess[ing]” over a few issues, such as abortion and gay marriage. He has critiqued unregulated capitalism as “an economy [that] kills.” And his landmark encyclical letter on the environment, “Laudato Si,” advocates both personal responsibility and government action to address threats to the environment.

Analysts speculate that these statements could matter to U.S. politics in part because Francis enjoys both wide popularity and high levels of awareness among U.S. Catholics. In polling from leading outlets, Francis’s approval among Catholics rests above 80 percent. And American Catholics seem to be following the pope closely. In the survey discussed below, two out of three Catholic voters in a national sample claimed to follow news about Francis either somewhat or very closely. Those two factors — awareness and approval – do suggest that this pope may be an effective leader of his American flock.

Does the pope influence Catholics more than some other spokesperson?

To test the effect of Francis’s statements, YouGov was commissioned to field a study that contrasted some of the pope’s notable comments with alternative messages and/or messengers regarding religion in American public life. As a part of the study, subjects were randomly assigned to read fictionalized, but true to life, newspaper stories featuring either Pope Francis or an alternative viewpoint. Because stories were assigned at random, any differences between the two groups of article readers after the stories should be due to the story that participants read.

First, the study compared the effect of an article reporting Pope Francis’s call for the church to find a “new balance” in public life with an alternative message stressing religious calls to prioritize “non-negotiable” policy issues, such as abortion and gay marriage.

On the whole, Catholic voters responded to the pope’s message, prioritizing policy issues more evenly and showing signs of moving beyond the “culture wars.” To give one example, 67 percent of Catholics who read the message about “non-negotiable issues” agreed that there is a culture war between religious and secular people in this country today, compared with 59 percent who heard the pope’s advocacy of a “new balance.”

BUCKLEY Figure 1

A second experiment, which was independently randomized, focused on the unique impact the pope might have through Laudato Sihis environmental encyclical. By contrasting the pope with generic “climate change experts,” the study identified new partners whom the pope’s message might reach more effectively than do traditional environmental advocates.

We wondered whether Catholics who attend religious services most regularly would be most likely to be affected by the pope’s statements. In questions before experimentation, the study found that weekly attendees were significantly more likely to claim that they had “heard a lot” about Laudato Si than non-weekly attendees (37 percent and 16 percent, respectively). The Pew Research Group has found much more support among weekly attendees for religious leaders “express[ing] their views on day-to-day social and political questions.”

BUCKELY Figure 2

Indeed, regular churchgoers were more likely to respond to the pope’s comments than other Catholics. Among all Catholics, agreement that human activities are responsible for climate change increased by a statistically insignificant margin after reading about the pope, from 51 percent to 55 percent.

BUCKLEY Figure 3

However, 54 percent of weekly attendees who read about the pope agreed that human activities were responsible for climate change, while that was true of only 41 percent of those who heard from the generic climate change expert. And 84 percent of weekly attendees who read about the pope agreed that humans have a moral duty to protect the environment, compared with 75 percent among those who heard from the climate change expert.

In contrast, the pope’s message had little effect among low attendees. Of the infrequent churchgoers who read about the pope, 55 percent thought that humans were responsible for climate change, compared to 57 percent who read about the climate change expert. This is not to say that the pope’s message was evaluated negatively. Rather, it had no more effect than an environmental message from a typical climate change activist.

Any “Francis Effect” on American Catholic politics will be more complex than these stylized experiments. The pope’s legacy will be as much defined by the leaders he selects for the American hierarchy as it is by his public rhetoric. But apparently Francis’s public teachings do matter to U.S. Catholics, particularly those most likely to be found in the pews.

David T. Buckley is Assistant Professor of Political Science and Paul Weber Chair of Politics, Science and Religion at the University of Louisville. YouGov conducted the study presented in this article in conjunction with Faith in Public Life and Catholic University in America’s Institute for Policy Research and Catholic Studies. A report detailing the study’s findings in more depth is available here.