Congolese president Joseph Kabila casts his ballot in the country's presidential election at a polling station in Kinshasa. File picture: Jerome Delay/AP.

Kinshasa - After two years of setbacks, broken promises and delays, the Democratic Republic of Congo on Wednesday effectively opened the starting gates for a crucial election that could alleviate -- or perhaps worsen -- the decades-long crisis gripping the vast central African nation.

"May the best person win," electoral board chief Corneille Nangaa said, pre-empting the official start of campaigning by a day.

Voters on December 23 will choose a successor to outgoing President Joseph Kabila, who has constitutionally remained in power as caretaker leader even though his second and final elected term ended nearly two years ago.

At stake in the vote is the political stewardship of a mineral-rich country that has never known a peaceful transition of power since independence from Belgium in 1960.

Eastern DR Congo is ravaged by decades of inter-ethnic bloodshed and militia violence, as well as a deadly Ebola outbreak, testing a large UN peacekeeping mission deployed in the country.

- Opposition candidate -

Twenty-one candidates are registered to vie to replace the 47-year-old Kabila, who has ruled since January 2001, after his father, president Laurent-Desire Kabila, was assassinated. 

Under international pressure against him seeking a third term, Kabila threw his support behind a chosen successor, Emmanuel Ramazani Shadary, in August.

Shadary is one of 15 Congolese individuals under European Union sanctions, accused of human rights violations when he was interior minister between December 2016 and early 2018.

One of Shadary's main rivals is Martin Fayulu, a little-known lawmaker who earlier this month was named the joint candidate of several -- but not all -- opposition parties that form a coalition in the parliament.

Fayulu arrived in the capital Kinshasa from Europe on Wednesday -- which also happened to be his 62nd birthday --  to launch his campaign to take the presidential Palais de la Nation.

"The joint (opposition) candidate is here. I am here," Fayulu told reporters after being greeted by hundreds of supporters.

Around half of DR Congo's population of 80 million are eligible to vote.

The electoral board is standing by its decision to use 106,000 touchscreen electronic voting machines supplied by South Korea, despite some opposition demands -- by Fayulu in particular -- for paper ballots.

- UN peacekeepers -

The government, which has a thorny relationship notably with the United Nations, has rejected all forms of international financial or logistical assistance for the election in a country nearly five times the size of France.

The UN peacekeeping force MONUSCO has proposed using its helicopters and planes to ferry imported voting machines to polling stations nationwide.

But Kinshasa wants to see MONUSCO gone by 2020, ending a 20-year presence including more than 16,000 pairs of boots on the ground at an annual cost of more than a billion dollars.

In Beni, a town in the east near the border with Uganda that has seen some of the fiercest conflicts in DR Congo as well as borne the brunt of the Ebola outbreak, residents expressed hope the election would bring better days.

 "Whoever is elected could maybe help us. The massacres might stop and we could return to our fields," said one local woman, Zawadi Kavugho.

Dieme Bumbere, a 21-year-old man unable to find work in Beni's moribund economy, said: "I think that if Kabila leaves power peace could come back."

Since September, Beni and its surrounding area has suffered a spike in raids by Allied Democratic Force (ADF) rebels, jihadist militiamen who kill, rob, kidnap and lay waste to villages.

Seven MONUSCO peacekeepers and a dozen Congolese soldiers have been killed in recent days while conducting a joint operation against the ADF, which has no identified leader or strategic goal.

Over the past four years, more than 700 civilians have been killed in attacks attributed to the ADF, mostly in fields, brushland or on the road leading to the nearest airport. 

The Ebola epidemic, which has claimed more than 200 lives, has only added to the rage and feeling of impotence.

Those fighting the outbreak -- Congolese health officials, the World Health Organisation, UNICEF, and Doctors Without Borders -- say their work is being hampered by villagers suspicious of vaccination programmes who throw stones and hit workers.

AFP