Putin announced his decision to lead Unified Russia during a speech on the second and final day of the party's congress on April 15 in Moscow.
"Working efficiently together, the government and the parliamentary majority make it possible to successfully develop the economy, improve health care and education, raise incomes, and strengthen our country's defense," a forceful-sounding Putin said, to thunderous applause. "I accept, with gratitude, the proposal put forward by party members and its leadership."
Putin has already said he will serve as prime minister when he turns over the presidency to his handpicked successor Dmitry Medvedev next month.
But analysts say it is the Kremlin leader's decision to become the head of Unified Russia that could prove even more significant. The move gives Putin a power base that should enable him to remain Russia's de facto ruler -- possibly indefinitely, if he so chooses. This is because Unified Russia is more than just a ruling party. It is the single reservoir of the country's political, business, and bureaucratic elite.Holding The Reins
In an interview with RFE/RL, Olga Kryshtanovskaya, head of the Institute for Elite Studies at the Russian Academy of Sciences, says that leading Unified Russia gives Putin control over most of the country's political establishment.
"He'll have the State Duma as a resource, since Unified Russia has a majority there," Kryshtanovskaya says. "He will have control over the Federation Council, where they also have a majority. He will have control over regional parliaments, because there they have a majority as well. These regional parliaments confirm the governors. His administrative resources will increase significantly."
Analysts say the emerging arrangement is beginning to resemble the Soviet system, in which actual power resided with the Communist Party, and high state posts -- like the president, prime minister, or leader of parliament -- were largely ceremonial. The general secretary of the Communist Party was the country's true ruler.
Kryshtanovskaya says the system has been "substantially modernized" to accommodate a market economy, and contains window dressing like carefully managed multicandidate and multiparty elections that give the appearance of plurality but ultimately keep power within the central party.
In essence, she says, Russia's evolving political system is taking nearly all its cues from the USSR. "This process can be called Sovietization in the most general sense," Kryshtanovskaya says. "Many mechanisms of the state machine are beginning to resemble Soviet ones. This includes the process of leadership recruitment, which will go through Unified Russia."Advantage, Putin
Putin's move also means that he will remain personally dominant in Russian politics even after Medvedev moves into the Kremlin.
Analysts have been divided over whether as prime minister Putin would be able to maintain control over Russia's political system and sprawling bureaucracy, given the enormous constitutional power Medvedev will enjoy as president. (Medvedev this week declined an invitation to join Unified Russia, saying such a move would be "premature.")
Lilia Shevtsova, co-chairwoman of the Russian domestic politics and political institutions project at the Moscow Carnegie Center, tells RFE/RL's Russian Service that Putin is now gaining political "weight and muscle" as he prepares for his post-Kremlin career.
"Imagine President Medvedev without a party, or as a rank and file member of the party, or even a member of its leadership," Shevtsova says. "But the leader of that party is Putin. Therefore in this tango for two, the disproportions will increase [in Putin's favor]. This will weaken the position not only of the president, but the presidency itself."
Shevtsova describes Unified Russia as being "like a glove on Putin's hand" throughout his presidency. It was formed in 2001 -- largely as a vehicle to support Putin's policies -- when the pro-Kremlin party Unity merged with Moscow Mayor Yury Luzhkov's Fatherland-All Russia.
There had been some speculation about whether Unified Russia's dominance would continue after his presidential term ended.
Stanislav Belkovsky, a political analyst who heads the Moscow-based Institute for National Strategy, tells RFE/RL's Russian Service that before Putin's ascent to the party leadership, top members of Unified Russia had been increasingly fearful of losing their privileges under the incoming regime.
"Unified Russia is not a party in the classical political understanding of that term. Unified Russia is a club of bureaucrats and businessmen who have one aim: access to the Kremlin trough," Belkovsky says. "Boris Gryzlov, the formal leader of Unified Russia, [deputy Kremlin chief of staff] Vladislav Surkov, and their comrades are very frightened that President Dmitry Medvedev will exclude them from the trough."
The new developments, of course, mean that that will most likely not happen. Shevtsova says having Putin at the helm gives the party "a second wind."
But in his acceptance speech, Putin indicated that his leadership comes with strings attached. The party, it seems, can expect changes in the near future -- possibly in the form of a Soviet-style purge.
"The party, as I have already said many times, should be reformed," Putin said. "Essentially, this is exactly what we're witnessing now. It must be more open to discussion, taking into account the views of the voters. It must be rid of bureaucracy, cleared of random people pursuing solely their personal goals and benefits."