By Steven Rosenberg BBC Moscow correspondent

President Putin - widely tipped to win and win easily

It is a Russian Mission Impossible: beat Vladimir Putin, whose approval rating tops 80%.

And with the Kremlin controlling the media, the purse strings and allegedly the whole election process, he is what they call in the races, a dead cert.

Perhaps that is why some of the country's most prominent politicians have decided not to run.

Like ultra-nationalist Vladimir Zhirinovsky who has taken part in every Russian presidential election since 1991.

This time he is backing a political unknown from his party - Oleg Malyshkin, the former boxer.

Communist Party leader Gennady Zyuganov, too, has bowed out. He is supporting left-wing candidate Nikolai Kharitonov.

Among the other hopefuls are a former chairman of the Central Bank, Viktor Gerashchenko and liberal politician Irina Khakamada.

The Kremlin is determined to ensure that President Putin beats them all hands down in the first round.

However, it is widely believed that Mr Putin's team has been actively encouraging opponents to stand against him, to prevent the poll from being seen as a farce.