Russia's Central Election Commission has registered three more candidates for the March 18 presidential election, raising the total number of candidates to six.
The commission on February 7 formally registered the candidacies of Boris Titov from the Party of Growth, Sergei Baburin of the Russian All-People Union Party, and Grigory Yavlinsky of the Yabloko party.
On February 6, the candidacy of Russian President Vladimir Putin was formally registered -- exactly two months after he announced his intention to seek a fourth term.
Kremlin critics say most of the other candidates are window-dressing in a vote Putin is certain to win in Russia's tightly controlled political environment.
Also officially registered are Vladimir Zhirinovsky, the leader of the Liberal Democratic Party of Russia, and Communist Party nominee Pavel Grudinin.
Others who have expressed intentions to run include TV personality Ksenia Sobchak and the leader of the Communists of Russia Party, Maksim Suraikin.
Russian opposition politician Aleksei Navalny, a vocal critic of Putin, has been barred from running because of a criminal conviction that he contends was the result of fabricated evidence.
Russia's constitution bars presidents from serving more than two consecutive terms.
Putin was first elected to an eight-year term as president in March 2000 after President Boris Yeltsin stepped down on the last day of 1999 and put Putin in charge as acting president.
From 2008 to 2012, Putin was Russia's prime minister. He was elected again to his current term as president in 2012.
Critics say Putin has rolled back democratic reforms and advances on human rights that were made during the 1990s after the collapse of the Soviet Union.
Detractors also accuse the former KGB officer of implementing Soviet-style methods to suppress dissent, and say he has needlessly stoked confrontation with the West.
Government critics also charge that election campaigns and results are manipulated by Russian authorities.
With reporting by TASS, Interfax, and Kommersant