KAMPALA, — On Sunday mornings, worshipers arrive two hours early to wait in line for one of 200 seats in the Missionaries of the Poor chapel. By the time Mass begins at 8 a.m., they have been joined by 2,000 more parishioners who sit outside in the sun.

Roman Catholic churches in Uganda are packed these days, the participants traditional-minded, their faith vibrant and strong.

Across Africa, the church reinforces the staunchly conservative values of a population that often attends services several times a week, for hours on end. Catholic leaders also provide homes and food for poor and disadvantaged people whom the state doesn’t help, including orphans, abandoned children, the homeless and the disabled.

Vatican officials announced Friday that cardinals from around the world would open a conclave Tuesday to choose a successor to Benedict XVI. Many wonder whether choosing an African would create a sense of excitement, drawing in new membership and reinvigorating the faith while ensuring that it stands firm on its conservative social mores.

But as strong as it is in Africa, the Roman Catholic Church faces stiff competition here from Pentecostal preachers whose charismatic services are closer to African tradition.

Catholicism on the rise in Africa

Among the Africans mentioned as having a chance to be elected pope are Ghana’s Cardinal Peter Turkson and Francis Arinze of Nigeria. Arinze, 80, had been considered a strong possibility to succeed John Paul II in 2005.

In the last century, the Catholic Church grew faster in Africa than anywhere else, with 16 percent of the world’s Catholics living on the continent, according to a Pew Research Center report.

The stark contrast between the church’s growth in Africa and decline in Europe provides perhaps the greatest logic for an African pope. Vatican statistics published last year showed 800 priests being added in Africa, while the number declined by 905 in Europe.

Whomever the cardinals finally choose, Ugandan church members hope their agenda — which decries Western social attitudes, particularly about homosexuality, while encouraging anti-poverty programs — will have informed the cardinals’ choice.

Turkson, for one, has linked the spate of child sex scandals in the Catholic Church in Western countries to homosexuality, saying taboos in African societies have prevented such abuses. In 2012, he opposed a United Nations call on African countries to ditch laws punishing homosexuality.

Pentecostal churches also on rise

But the church faces increasing competition from Pentecostal churches. Many are one-person operations founded by men who declare themselves pastors or bishops and claim to cure the sick or resurrect the dead, luring converts from more traditional churches.

The Catholic Church, staid and traditional, lags behind Pentecostals who have proved to be masters of taking advantage of public sentiment over a popular 2009 bill in Uganda to institute the death penalty for homosexual rape or acts with children, said James Onen of Freethought Kampala. The Vatican opposed the bill.

“The Pentecostal churches will do whatever it takes to fill the pews, as opposed to the Catholic Church, which remains more rigid, structured and hierarchical,” Onen said.

Pentecostal churches allow parishioners to dance, sway, speak in tongues and experience what they believe are miraculous cures, closer to charismatic African tradition.