Russia's Vladimir Putin has named Dmitry Medvedev as his preferred successor in the presidential election on 2 March. Mr Putin plans to become prime minister after the election - if Mr Medvedev, the clear favourite, wins.
Here BBC Moscow correspondent Richard Galpin profiles the four hopefuls vying to succeed President Putin.
One prominent opposition politician is barred from the race, while another one has abandoned his bid.
DMITRY MEDVEDEV (United Russia Party)
Mr Medvedev sees himself as pragmatic and business-friendly
Mr Medvedev, a first deputy prime minister, is President Putin's chosen candidate and he is expected to win by a huge margin. Opinion polls indicate he could get anything up to 82% of the vote.
Just 42 years old, he hails from President Putin's St Petersburg clan. Mr Medvedev and President Putin have apparently known each other for at least 17 years.
A lawyer by training, he has risen very rapidly under Mr Putin ever since he moved to Moscow in 1999.
He ran Mr Putin's first election campaign the following year and then in 2003 became Kremlin chief-of-staff, before taking up his current position as first deputy prime minister in 2005. He is also chairman of the state-controlled energy company Gazprom.
Some view him as being more liberal than President Putin, at least in the sense that he does not have a background in the Russian secret services.
He also has considerable experience dealing with economic issues.
But the big question mark over Mr Medvedev is whether he is being promoted simply because he will do what he is told by Prime Minister-to-be Vladimir Putin.
He is certainly very diffident in the presence of Mr Putin and has no support base of his own.
He has pledged to keep the country on the same course, but has indicated there will be a greater emphasis on social issues such as education and health as well as on fighting corruption.
GENNADY ZYUGANOV (Communist Party)
Gennady Zyuganov has described capitalism as "barbaric"
Mr Zyuganov, who is now 63, is a veteran of Russian and Soviet politics.
He reached his peak in the presidential election in 1996, when he came close to defeating Boris Yeltsin. Mr Zyuganov won almost a third of the votes, forcing the election into a much-disputed second round.
He also gave Mr Putin a good run for his money in the 2000 presidential race.
Since then he has seen his popularity decline dramatically and current predictions indicate he will only take between 6% and 15% of the vote.
He is a good communicator and much of his support comes from the elderly. But in modern Russia, the elderly are a rapidly declining breed.
Critics accuse Mr Zyuganov of selling out to President Putin, pointing to how little he has criticised the Kremlin's domestic and foreign policy.
But after December's parliamentary election, won by the ruling United Russia Party (URP), he was bitterly critical of the authorities, saying the election was the dirtiest on record.
He has pledged to re-nationalise the country's resources and strategic industries, saying: "We must return to the people the wealth stolen from them in the thievish 1990s". He describes capitalism as "barbaric".
VLADIMIR ZHIRINOVSKY (Liberal Democratic Party)
Mr Zhirinovsky has a record of anti-Semitism but his father was Jewish
Mr Zhirinovsky is the showman of Russian politics. He espouses an ultra-nationalist, anti-Western ideology and has a record of anti-Semitism.
Now 61, he only admitted in 2001 that his own father was Jewish, after his origins had been uncovered by the media.
He is known for starting fights inside parliament and on television and has been accused of being a tool of the secret services, although he denies this.
The LDPR, which he founded in 1990, did well initially. But, like all other parties, it has been marginalised by the Kremlin-created URP, which today controls more than two-thirds of the Duma (lower house of parliament).
Mr Zhirinovsky is fond of political stunts aimed at tapping into the prevailing popular sentiment.
His most recent was to recruit Andrei Lugovoi, the main suspect in the poisoning of former KGB officer Alexander Litvinenko, to run as LDPR candidate in the parliamentary election. Mr Lugovoi won a seat and is now immune from prosecution.
Mr Zhirinovsky is regarded as a Kremlin loyalist.
His policy platform includes defending Russia from external enemies and ensuring the Russian army is strong.
Opinion polls indicate he could take up to 11% of the vote.
ANDREI BOGDANOV (Democratic Party)
Andrei Bogdanov wants to take Russia into the European Union
Mr Bogdanov is the mystery candidate.
He is 37, almost unknown and has a blog with holiday photographs of him in his swimming trunks.
With his long slicked-back hair, he looks more like a 1980s rock musician than a politician.
His Democratic Party won 90,000 votes in the parliamentary election.
And yet Mr Bogdanov apparently managed to collect the two million signatures he needed to register as an independent candidate for the presidential election.
He is accused of being backed by the Kremlin, with the aim of splitting the opposition vote.
It has been reported that he was previously a senior member of the URP.
One of his main pledges to the electorate is to take Russia into the European Union.
Opinion polls indicate he will get 1% of the vote.
EXCLUDED OPPOSITION LEADER
Mikhail Kasyanov, aged 50, was barred in January from running in the presidential election after prosecutors said they had found too many invalid signatures in his list of supporters.
An ex-finance minister under Boris Yeltsin, he was appointed prime minister by Mr Putin in mid-2000, but the pair fell out and Mr Kasyanov was sacked four years later.
In April 2006, he was elected chairman of the opposition People's Democratic Union (PDU) and helped organise the so-called "dissenters' marches" that were violently suppressed by police.
Another opposition leader, Garry Kasparov, aged 44, abandoned his bid in December, citing difficulties in arranging for supporters of his The Other Russia bloc to meet in Moscow - an official requirement for his candidacy.
Mr Kasparov is a former world chess champion who retired from the game in 2005 to focus his efforts on defeating President Putin.
Born in Baku, Azerbaijan, he became the youngest world chess champion in 1985, before going on to dominate the game for the next two decades.