The Financial Times publishes the most extensive list that has appeared in foreign press of candidates that could potentially succeed Mr. Putin. Apart from Mr. Ivanov, Russia's former defense minister and current first vice-premier, the candidates are as follows:
Head of Russian Railways and a close confidante of Vladimir Putin from his St Petersburg administration days. Spent time as a diplomat, prompting speculation that he had KGB links. Not associated with the siloviki or the liberal group in the Kremlin, and has an independent power base in Russian Railways, one of Russia's most strategically important enterprises.
General director of Rosoboronexport, the arms export monopoly. Served as a company representative in the 1980s in Dresden, East Germany, where he told an interviewer he lived in the same apartment block as Mr Putin. Has a power base in Rosoboronexport, which has taken control of the massive Avtovaz, maker of Lada cars.
Deputy prime minister (since February 2007) responsible for external economic activity. Another Leningrader who got to know Mr Putin in the city mayor's office. Regarded as highly competent and close to the Kremlin siloviki. Mr Naryshkin's recent promotion sparked speculation that he could emerge from the shadows as
Mr Putin did in 1999.
Despite Mr Putin's consistent denials that he might seek a third term, the idea refuses to die; the speaker of Russia's upper parliament house called again last month for constitutional change to allow him to run. Has promised to retain "influence" after stepping down - and has never ruled out the theoretical possibility of returning as president in 2012.
Joint favourite comes from a rival clan in the Kremlin
Mr Medvedev is both first deputy prime minister responsible for Russia's "national projects" - multi-billion-dollar social investment programmes - and chairman of Gazprom, the gas monopoly. He is seen as associated with a liberal Kremlin faction.
Like many around the president, he was born in Leningrad - and studied law, like Vladimir Putin, at Leningrad State University. He got to know Mr Putin as a legal adviser in the St Petersburg administration in the 1990s. Previously Mr Putin's Kremlin chief of staff, he was handed the national projects dossier in November 2005 - a potential vote-winner that could turn out to be a poisoned chalice if the projects fail to deliver.