YAOUNDÉ, Cameroon – When 93-year old Zimbabwean President, Robert Mugabe, staggered to the podium to address the UN General Assembly last week, observers were quick to point to the president’s failing health and advancing age as reasons why he should not run for re-election next year.

Mugabe – who was a leader in the struggle against the unrecognized white-led government of what was then known as Rhodesia – has been at the helm of the nation since it was officially given independence in 1980: First as prime minister, and since 1987, as president.

Zimbabweans will go to the polls in 2018 in what promises to be one of the tightest races in the country’s checkered political history.

Mugabe says he will again run for office, but he may be facing a stern challenge from a “grand coalition” of opposition political parties bent on getting the nonagenarian authoritarian leader out of the way.

Zimbabwe – one of Africa’s most prosperous nations at independence – has been facing a decades-long economic crisis. It suffers from high unemployment, loss of capital, a breakdown in public services, and a diminishing money supply, which has led to some debts being settled through barter.

Mugabe’s regime has also been accused of harassing the opposition and ignoring the rule of law.

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Among those urging a change in the country’s ways are the nation’s Catholic bishops, who issued a letter on the elections at Pentecost, which was reissued earlier this month on the bishops’ conference website.

“Let us, in this pre-election period, allow access for all contesting parties to the media…so that we may have a healthy public debate on the issues that affect us today,” the bishops wrote, noting “an athlete is not crowned unless he or she competes according to the rules.”

The bishops also called on the Mugabe government to “align out laws so that they harmonize with our constitution.”

The bishops said it was the duty of the government to educate voters on the process of voting, including how to register to vote.

Some Catholic clergy are making a direct appeal to their flock, especially young people, to create a change in the country.

“Youths, it is your time now to change the face of Zimbabwe politically. Do not let the old leaders continue making depraved decisions for you,” said one Catholic priest.

Father Rungano Muchineripi read the letter from the bishops after a church service in St. James Catholic Church in the Emerald Hill neighborhood of the capital Harare.

He told AllAfrica.com it was time Christians stopped simply praying and hoping that things could get better, and said Christians need to register and vote for “a people oriented government which is not evil.”

The priest told the news website it was a sin not to vote.

“Zimbabweans have been reduced to paupers by an irresponsible government that is corrupt and evil. There should be massive voter education campaigns now,” Muchineripi said.

The chairperson of the National Catholic Youth Council, Tendai Karombo, said there is a need to organize workshops for young people to drill them on what they need to do to take part in the electoral process, including voting.

“We are Christians and our ways cannot be separated from our politics. When you know what is expected of you as a Catholic, let your voice be heard through the ballot box,” he told the Daily News.

“We are working with the Catholic Commission for Justice and Peace (CCJP) to make us understand how to vote from the Catholic perspective,” Karombo said. “I would want to encourage youths to be the candle that lights in the dark, promoting peace and unity, exercise the right to vote and doing so in peace.”

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The strong stand by Catholic organizations could present problems for Mugabe next year. Although Catholics make up just under 10 percent of the population, over 80 percent of the country is Christian, and the Catholic Church is considered a powerful voice in national affairs.

Mugabe is also facing a more unified opposition than he has in previous years: The “grand coalition” is attempting to pull together a hodgepodge of around 40 political parties, whose disunity has benefited Mugabe in the past.

(The president says he actually prefers a united opposition, telling supporters it will spare the ruling ZANU-PF party the task of devising several strategies to deal with each candidate. “It will just be one blow and they are done,” Mugabe said.)

However, the opposition is finding it hard to determine who should run for president. The leading candidate is longtime opposition leader Morgan Tsvangirai, head of the Movement for Democratic Change Zimbabwe. His strong showing in the 2008 election forced Mugabe into a unity government in which Tsvangirai served as prime minister – although Mugabe circumvented the agreement, and Tsvangirai exercised little actual power.

The unity government ended after Mugabe won the 2013 election.

Tsvangirai is facing a challenge from Joice Mujuru, a former vice president in Mugabe’s government who was purged by Mugabe in 2014 (a common fate for Mugabe underlings who are seen to be too popular); and Welshman Ncube, the leader of the Movement for Democratic Change, which Tsvangirai left in 2006 after an intraparty squabble (Tsvangirai’s following is much larger).

Tsvangirai has been endorsed by seven other parties, and is said to be ironing out the details to get the other two contenders to agree to letting him lead the opposition ticket.

Tsvangarai has said it is time for the opposition to stop the bickering and take down Mugabe, whom he accused of ruining the Zimbabwean economy.

The bishops also lamented the country’s current state.

“There is no reason for anyone to be short of food or clothing or work or housing or education or healthcare or water,” the bishops wrote in their statement. “There is not a person in Zimbabwe who does not want growth and a better life for their children. But it will not happen unless we become engaged in the struggle to make it happen. We have all the resources so that each one can find the fullness of life.”

As preparations continue for the 2018 election, there are reports of political violence already taking place across the country, which the opposition and human rights groups blame on the government.

The country’s bishops have cautioned against violence.

“As we prepare for 2018, let us respect each other and even mirror in our words and actions the love of God, Father of us all,” the bishops said in their statement, adding it was necessary for the state and the citizenry to “promote national unity, peace and stability.”

They said violence and coercion would “only serve to discredit our elections.”

Although many believe 2018 might be the year that Zimbabwe finally sees the back of Mugabe, his supporters say the president is going nowhere.

Grace Mugabe, his wife and possible successor, told reporters people will vote for him even if he runs “as a corpse.”