TUCSON, Ariz. — In recent years, the Roman Catholic Church has taken a more active role in pushing for an immigration overhaul that would legalize the millions of men, women and children who are in the country illegally. Clergy have preached from the pulpit about welcoming “the stranger.” Church leaders have staged fasting and prayer events to spotlight the plight of the immigrant.

They’ve even created prayers for “safe migration” to be said out loud by the congregation during Mass — all in hopes of persuading parishioners to support what they call a humanitarian cause.

However, it’s unclear how the message has been translated from the church pews to the halls of power in Washington.

That’s why church leaders are taking a more aggressive approach starting Sunday at Masses throughout the country.

Unlike a “Justice for Immigrants” program conducted in 2006-2007, this time church leaders are urging Catholics to call, write and e-mail their congressional representatives, even providing prewritten letters and electronic postcards. Congress returns from its summer break Monday, and although an immigration bill passed the Senate, it faces tough opposition, mainly from Republican lawmakers, in the House.

Kevin Appleby, director of immigration policy at the U.S. Conference of Catholic Bishops, said the latest immigration overhaul campaign is larger, bolder and a more unified national effort than in years past.

“We learned some lesson from 2006, 2007,” Appleby said. “You really have to mobilize constituents and voters in order to succeed.”

Polls show that there is broad support among Catholics for immigration reform, Appleby said. The challenge is getting those people to take action.

“Translating the support to action is the goal,” he said.

On Sunday, Catholic dioceses across the country will start holding events about the need for an immigration overhaul, Appleby said.

The conference’s Committee on Migration is urging bishops throughout the country to address immigration at Mass, providing them with talking points and suggestions for homilies, bulletin inserts and pulpit announcements-all available via the Internet.

“We’ve urged the bishops to focus on this time frame,” Appleby said of the month of September. “It’s a critical time. We need to get the Senate bill through to the House. It needs a push. We’re doing everything right now to keep the pressure up.”

In June, the Senate passed a comprehensive immigration bill that would provide a pathway to citizenship for an estimated 11 million people living in the country illegally. The bill also calls for a $46-billion border security package. However, it remains unclear whether the bill will ever be taken up in the House.

Archbishop Jose Gomez of Los Angeles, chairman of the Committee on Migration, is strongly urging all priests in his diocese to focus on immigration reform in Sunday’s Mass. Other church leaders have staged pilgrimages and some have met or plan to meet with decision-makers in Washington to press their cause.

The material made available by the bishops conference emphasizes biblical teaching on caring for the unfortunate and oppressed. For example, the bishops quote a number of passages from Scripture, such as Exodus 23:9:

“You must not oppress the stranger; you know how a stranger feels, for you lived as strangers in the land of Egypt.”