Voters in Congo are heading to the polls to elect a new president in what is hoped to be the country’s first democratic change of power in roughly 50 years.

A total of 21 candidates are vying for the mineral rich but poverty-stricken nation’s highest office on Sunday.

But only three of them are expected to have a chance of winning: Ruling party candidate and protege of outgoing President Joseph Kabila, Emmanuel Ramazani Shadary, and opposition candidates Felix Tshisekedi and Martin Fayulu.

The Central African nation will also elect a national assembly.

Initially set for December 23, the polls were postponed by a week after a fire – believed to have been set deliberately – destroyed 8000 voting machines in a warehouse in the capital Kinshasa.

Voters in the Democratic Republic of Congo queue on Sunday. Photo: AFP/Getty

The presidential election has already been delayed for two years by Mr Kabila, who has been in power for 17 years.

In addition, the electoral commission earlier this week delayed elections in three towns until March 2019 due to an ongoing Ebola epidemic and violence.

The decision comes despite the fact the new president is due to be sworn in on January 18, essentially meaning that votes cast in these areas – two of which are opposition-inclined – will essentially be null and void.

The atmosphere in Congo has been heating up ahead of the vote, with at least 10 people killed in clashes with security forces and ruling party supporters at political rallies across the country.

About 39 million eligible voters are able to cast their votes at roughly 60,000 polling stations across the country.

Results are expected within a week after the polls.