Guinea-Bissau has a history of coups, mutinies and uprisings since independence in 1974.  It has since become a hub for cocaine smuggling from South America to Europe, BBC news said.

The head of the European Union's observer team, Johan Van Hecke, said that the drug trade had been a major campaign issue. "There have been some very inflammatory statements made by some political leaders accusing each other of being directly or indirectly involved in drug trafficking and for accepting money from people who are responsible for drug trafficking to fund their campaigns," he said.

In order to fight the drug traffickers, Guinea-Bissau desperately needs strong political leadership, which has been severely lacking as personal animosity has dominated politics, the report said. There was hope that a power-sharing agreement signed last year would give President Vieira the political support to tackle the immense challenges facing the country.

Sunday's election is expected to be dominated by four parties - the Republican Party for Independence and Development (PRID), which was formed ahead of the election by former Prime Minister Aristides Gomes; the historically dominant African Party for the Independence of Guinea-Bissau and Cape Verde (PAIGC); the Social Renewal Party (PRS); and the Development, Democracy and Citizenship Party (PADEC).

One positive development of the campaign, according to Van Hecke, has been the apparent absence of the army, upon which politicians have traditionally relied for power. While international observers keep a close eye on the election, the drug barons are all too aware that the longer the political crisis continues, the easier it will be for them to increase their grip on Guinea-Bissau.