It would seem that Roman Catholics challenging the ban on married priests have found a leader in Archbishop Emmanuel Milingo.

He's defiantly appeared with his bride from a 2001 wedding where hundreds of couples tied the knot. He stood his ground last month after being excommunicated for installing four married men as bishops.

But the 76-year-old prelate from Zambia finds himself more shunned than celebrated, even by his ideological allies.

Many of the established movements pushing for optional celibacy are keeping a cautious distance. Milingo's flamboyant style and unusual associations — including the Rev. Sun Myung Moon — are simply too edgy for those trying to work within the system to alter centuries-old church views on marriage and the priesthood.

It's another example of how head-on defiance of the Vatican, whether the issue is openly gay clergy or ordinations of women, can attract widespread attention but often winds up putting anti-status quo forces on the fringe of the debate.

The "married priest" groups, led by American Catholics, mostly favor a different strategy: seeking to avoid direct clashes with Rome. Instead, they believe time is on their side.

They predict the Vatican may be forced in coming decades to seriously consider married clergy because of pressures including declining vocations and more tolerant views from the next generation of bishops.

"The general feeling is that Milingo is a bit too 'out there' for us. Do we really want to tie our future to a loose cannon?" said Bob Motycka, who served for nearly two decades as a Chicago-area priest before leaving to marry in 1998. He now helps lead a group known as Weorc — the Old English word for "work" — that includes nearly 2,000 men who were ordained priests and later wed.

"People have shied away from Milingo for the same reason they shy away from people calling for schisms or those hanging out a shingle and starting a breakaway church," he said. "Yes, we are dissident, but we still remain faithful and loyal to the church."

Such a straddle is possible because priestly celibacy is a long-held practice but not immutable doctrine. In early Christianity, there was no formal ban on marriage for clergy. The Bible mentions St. Peter's mother-in-law and many scholars suggest other apostles had wives — as well as at least some popes such as the 9th century Hadrian II.

In the early Middle Ages, however, movements for celibacy gained momentum and it became a requirement by the 12th century.

The Vatican grants some loopholes, including giving full status to married priests who convert from Anglicanism and selected other denominations. Eastern Rite churches, which follow Orthodox traditions but are loyal to the papacy, also permit ordination of married men in their historical homelands in the Middle East and Eastern Europe. But the Vatican has strongly resisted calls for broader openings despite some rising voices.

Last year, one of France's most respected Catholic figures, Abbe Pierre, wrote that he favored allowing priests to marry. In 2003, more than 160 priests in the Milwaukee Archdiocese signed a letter supporting married clergy.

Most groups estimate there are at least 25,000 men in the United States who left the active priesthood to marry, and between 100,000 to 150,000 worldwide. The church considers them outcasts. Some totally drop out of religious life. But others continue to independently carry on rites such as marriages even though they are not considered valid in the eyes of the church.

The Vatican often ignores such acts. Milingo, however, crossed one of the red lines.

The church comes down hard on any unauthorized ordinations and, especially, installations of bishops. The reason is fear of a snowball-effect schism: the maverick bishops creating more like-minded priests and bishops, and so on. Milingo ignored Vatican appeals and in Washington on Sept. 24 installed four married men as bishops who claim affiliation with the breakaway Synod of Old Catholic Churches. Milingo and the four men were excommunicated.

Milingo has been in escalating disputes with the Vatican since 2001 when he was married to a South Korean acupuncturist chosen by Moon's Unification Church. Milingo later renounced the union, but has apparently reunited with his wife — who attended a conference last month in New Jersey organized by Milingo's group Married Priests Now!

No one expects any major changes on celibacy under Pope Benedict XVI. But some are heartened by the pope's desire to reopen doors, including talks with the ultraconservative Swiss-based Society of St. Pius X. The Vatican excommunicated its founder, the late Archbishop Marcel Lefebvre, in 1988 after he consecrated four bishops without Rome's consent.