With Los Angeles Cardinal Roger Mahony prominently among them, many of the nation's senior Roman Catholic bishops are nearing mandatory retirement, offering the Vatican a significant opportunity to reshape the American church.
In Los Angeles, home to the country's largest Catholic archdiocese, the shift could open the way for a bishop to become the first Latino cardinal in the United States. Three Latinos, two from California, already are rumored to be possible successors to Mahony, 73.
Nationwide, the retirements will provide Pope Benedict XVI a chance to put his stamp on a church that is struggling to serve growing ranks of immigrants and recover from clergy sexual abuse scandals.
Nearly one-third of 265 active U.S. bishops must submit letters of resignation to the pope within five years because they will have reached the mandatory retirement age of 75. More than half the bishops will reach the milestone within 10 years.
The roster of upcoming resignations includes several of the country's most influential prelates, including Chicago Cardinal Francis George, 72, the current president of the U.S. Conference of Catholic Bishops, and Philadelphia Cardinal Justin Rigali, 73, who sits on a powerful Vatican panel that recommends bishop candidates to the pope.
Also on the list is Cardinal William J. Levada, 72, the former archbishop of San Francisco who is now the Vatican's chief theologian and point man on cases of sexual abuse forwarded by bishops worldwide.
Most of the retiring bishops will probably remain on the job for a year or more after their 75th birthdays while successors are found. The pope ultimately decides when to accept the resignations.
Church scholars say the departures of so many high-level prelates -- a coincidence as well as a rarity -- will open the door to a new generation of leaders unencumbered by the U.S. Catholic Church's sexual abuse crisis, which has led to more than $2 billion in legal settlements.
"So much of that fresh start depends on how the successor handles the problems" in each diocese, said the Rev. Anthony Pogorelc, a sociologist of religion at the Catholic University of America. "It will depend on transparency."
The impending change in leadership comes as the U.S. church confronts a serious shortage of priests and demographic changes that are dramatically altering the composition of the nation's Catholics, an estimated 64 million.
The number of Catholics is shrinking in the Northeast, leading to the closing of parishes and schools, even as Catholic populations balloon in the southern and western parts of the country because of Latin American immigration.
Latinos make up more than one-third of the U.S. Catholic population and will probably become a majority in the next decade, according to figures provided by the Conference of Catholic Bishops. Immigrants from Asia, Africa and Eastern Europe are adding to the ethnic and racial mix.
"The future of American Catholics is one of rich diversity," said Matthew Bunson, editor of the Catholic Almanac.
Responding to that diversity, Bunson said, "is going to be one of the major strategic pastoral questions for the church in the 21st century."
Nowhere are these forces more evident than in Los Angeles. The three-county archdiocese has more than doubled in size over the last 30 years, now surpassing 4 million Catholics, according to the Catholic Almanac. That's nearly twice the size of the next largest archdiocese, in New York.
L.A.'s phenomenal growth has been driven largely by Latinos, who make up 75% of the archdiocese's population, a spokesman said.
During more than two decades as head of the Los Angeles archdiocese, Mahony has earned scorn for his handling of sex abuse scandals but praise for integrating Latinos and other immigrant communities into the church and for his advocacy of immigrant and migrant rights, issues he has embraced since his days as a priest. Many Latinos see the Spanish-speaking cardinal -- who is of German-Italian ancestry -- as one of their own.
Mahony declined to comment. But church scholars say it is only a matter of time before a Latino is named archbishop, and eventually cardinal, in Los Angeles, long considered the second-biggest prize in the U.S. Catholic hierarchy, after New York.
Although decisions about bishops are made secretly in Rome, the names of at least three possible Mahony successors have begun to circulate: Sacramento Bishop Jaime Soto, 53; San Antonio Archbishop Jose Gomez, 57; and Monterey Bishop Richard John Garcia, 61.
The three come from a slim field. Just 26 of the nation's active bishops are Latino, according to the Center for Applied Research in the Apostolate. The number of U.S. Latino priests -- who can eventually join the ranks of bishops -- is even thinner: Roughly 3,000 of approximately 41,000, or 7%.
The Vatican's ambassador to the United States, Archbishop Pietro Sambi, declined to comment.