Six challengers lined up for Algeria's presidential election. While the incumbent, Abdelaziz Bouteflika, was favourite at the start of the campaign, observers said he faced stiff opposition, in particular from his former prime minister.
The 60-year-old Ali Benflis was Algeria's prime minister from August 2000 to May 2003.
Ali Benflis is regarded as a serious challenge to the incumbent
A former lawyer and state prosecutor, he was justice minister from 1988 to 1991. He was also a founder member, in 1987, of the government-sponsored Algerian Human Rights League.
Mr Benflis ran Mr Bouteflika's 1999 presidential election campaign and later became his chief presidential aide.
But the president sacked him as prime minister in May 2003, after he used his leadership of the FLN (National Liberation Front) to promote his own presidential bid.
An FLN faction close to President Bouteflika turned against Mr Benflis. Since then the FLN's assets have been frozen, pending a court decision.
Mr Benflis is running on a platform of social and economic reforms, relying on support from his wing of the FLN.
Observers says he is poised to win a second term in office
Born in 1937, Abdelaziz Bouteflika has been president of Algeria since 1999. He served as foreign minister for 16 years until 1978. He went into self-imposed exile in 1981.
He returned to Algeria and to politics in the late 1980s. In 1994 the army offered him the presidency without power over the military, but he declined.
The military backed him in the 1999 presidential election. Since then he has tried to play down his image of a president under the army's thumb.
He was elected on a promise to restore peace after years of conflict with armed Islamists over the cancellation, in January 1992, of elections which the Islamic Salvation Front or FIS was poised to win.
In September 1999 Algerians voted in a referendum for his Civil Concord initiative. This formalised a ceasefire signed with the armed wing of the FIS in 1997.
President Bouteflika has repeatedly said he wants to take the Civil Concord further to what he calls "National Reconciliation". Many see this as a strategy to rehabilitate the FIS and negotiate peace with other armed groups.
He has promised wide-ranging reforms of the economy, education and the justice system. But the opposition says he has failed to deliver.
Saad Abdallah Djaballah
Djaballah has built a reputation of being an independent leader
The youngest of the presidential contenders, 48-year-old Abdallah Djaballah leads the Movement for National Reform (MRN).
Also known as Islah, this is a radical Islamic party which aims to build an Islamic state while remaining a player in the democratic electoral process.
His commitment to orthodox Islam and consistent criticism of the authorities has won him substantial support among Islamic voters. His party is currently the third largest force in parliament after making gains in the 2002 general elections.
Djaballah was one of six candidates who pulled out of the 1999 presidential race hours before polling began.
The rejection of the candidacy of another Islamist, Ahmed Taleb Ibrahimi, is expected to boost Djaballah's chances.
The first ever woman to bid for the presidency, Louisa Hanoune is a lawyer who began her political career as a women's rights activist.
Hanoune is the first woman to seek presidency in Algeria
She was jailed soon after she joined the Trotskyist Social Workers Organisation, an illegal party, in 1981, and again after the 1988 youth uprising. She now heads the same organisation, renamed the Workers Party (PT).
Known as an eloquent speaker, Louisa Hanoune is widely admired both for her criticism of the authorities and her advocacy of a law-based democratic government, from which radical Islamists should not be excluded.
Her personal reputation as an accomplished politician is not matched by that of her party, which remains on the sidelines.
Though never a major player on the political scene, Rabaine has been an opposition activist for many years.
The decision by Berbers to boycott the poll my affect his chances
He was one of the founders of the independent Algerian Human Rights League in 1985 and was jailed several times.
He leads a small party, Ahd 54, meaning Oath 54.
This is a reference to the principles espoused by the FLN (National Liberation Front) when it led the war of independence.
Sadi is well established but his influence is mostly felt in Kabylia region
A former human rights activist and campaigner for the Berber culture and language, Said Sadi is a psychiatrist by profession.
He is a staunch adversary of the Islamists and a supporter of a secular state.
His party, the Rally for Culture and Democracy (RCD), was briefly a junior partner in the first coalition government formed by President Bouteflika.
Said Sadi is seen as close to the army generals who, in 1992, cancelled general elections which Islamists were poised to win. He came third in the 1995 presidential elections, with under 10 per cent of the vote.
Said Sadi has consistently called for a radical overhaul of the political establishment and a chance for the post-independence generation to lead the country. His opposition activities earned him a short spell in prison in the 1980s.
BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.