Putin might pick one of his first deputy prime ministers, Sergei Ivanov and Dmitry Medvedev, or he might go with State Duma Speaker Boris Gryzlov or Federation Council Speaker Sergei Mironov, said the spokesman, Dmitry Peskov.
Putin's huge popularity among voters means victory is virtually guaranteed for whichever candidate he supports in the presidential election in March. But Putin has so far given no clues as to whom he will back.
"The president has the right to say 'I think this guy is best' and give him a boost by sharing with him his unimaginable popularity," Peskov told journalists Wednesday evening.
"But this should indeed be a figure well-known to voters," he added, without elaborating.
In June, senior Kremlin aide Igor Shuvalov suggested that Putin might go for a surprise choice. But Peskov's comments Wednesday, to an invited group that included foreign media, appeared to rule this out.
He said either Medvedev or Ivanov, widely seen as the most likely successors, "can be a successful candidate" but urged reporters "not to forget about party leaders who are becoming increasingly popular."
The two key party leaders are Gryzlov, head of the main pro-Kremlin party United Russia, and Mironov, leader of A Just Russia, a new pro-Kremlin force aiming to steal votes from the Communists and nationalists.
The campaign for Dec. 2 Duma elections kicks off this weekend, and the Kremlin hopes to secure a parliament dominated by United Russia and A Just Russia. The Communists and possibly nationalists are likely to take the remaining seats. Changes to election rules have made it unlikely that the country's increasingly marginalized liberal opposition will win representation.
"The main competition will be between the heavyweights," Peskov said. "I think at least three parties will rally the 7 percent of the vote needed to win parliamentary seats -- United Russia, A Just Russia and the Communist Party."
The latest opinion polls indicate that Vladimir Zhirinovsky's Liberal Democratic Party, which has generally backed the Kremlin, is not certain to enter the Duma.
Peskov acknowledged that the absence of a strong opposition in the parliament was a drawback of the political system, but said the Kremlin was not to blame.
"The existence of a well-organized opposition is important for the government of any country, and I am sure this process will develop," he said.
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