The election is expected to sweep all of the Kremlin's liberal democratic opponents out of the legislature. It will almost certainly cement the dominance of a single party, United Russia, for at least the next four years. And it will allow Putin to claim a mandate from the Russian voters to remain the country's leader, even though under the constitution he is ineligible to seek re-election.
Polls predict Putin's party could win two-thirds of the popular vote and 80 percent of the 450 seats in the legislature. A smattering of seats, meanwhile, may go to the Communists, the ultra-nationalist Liberal Democratic Party of Russia and, perhaps, a left-leaning party also led by Kremlin loyalists.
All but the Communists would be expected to vote in lockstep with the Kremlin.
If anything, though, the polls may underestimate the scale of United Russia's expected victory.
The Kremlin has mounted an extraordinary effort to pressure Russians to vote - and to ensure they choose the party list of United Russia, headed by Putin himself. Many opposition groups have denounced that effort, saying the Kremlin's allies are using coercive or repressive tactics to ensure United Russia wins in a landslide.
For supporters of the Kremlin, a runaway victory for United Russia would mark a victory for stability and order, and vindicate Putin's nearly eight-year effort to build a powerful central government at the expense of regional governments, the courts, parliament, the media and other nominally independent institutions.
The Kremlin's foes say the vote will signal the triumph of Russia's powerful bureaucracy and the so-called "siloviki," veterans of the intelligence and military services who have been appointed to key government posts by Putin, himself a former mid-ranking KGB officer. In the long run, they argue, a victory for Putin will weaken Russia and further divide it from the West.
Most expect the vote to help settle the most urgent political question facing Russia, the crisis of succession to the Russian presidency.
The larger the turnout and the bigger the victory for United Russia in Saturday's elections, most analysts here agree, the easier it will be for Putin to claim the right to lead Russia after his current presidential term ends.
The 55-year-old incumbent appears to be in good health and is overwhelmingly popular, with approval ratings consistently above 80 percent in recent months. But Putin is prevented by the constitution from seeking a third consecutive term in the March 2 elections.
While polls show most Russians would support changing the constitution to permit Putin to run again and many have begged him to do so, he has repeatedly promised to step down.
Putin explained his reluctance to run again in an October 2005 interview with journalists from the Netherlands.
While conceded he was concerned his successor might falter, he said: "If each successive head of state were to change the constitution to suit them, we would soon find ourselves without a state at all."
But Masha Lipman of the Carnegie Moscow Center said that Putin holds a unique position in Russian society as the only figure capable of settling disputes among the various factions and so-called "clans" that control Russia's government and major industries.
Mainly, she said, that's because he and his allies have "radically emasculated" the institutions - the courts, parliament, media - that perform this task in Western-style democracies.
That has left Putin with powers rivaling those of a czar.
"He's almighty," she said.
As a result, Putin's scheduled departure from office would create a power vacuum that is viewed with deep foreboding among Russia's political and economic leaders.
Thanks to the Kremlin's control of the media, there are no independent political figures with the stature or the means to mount a credible campaign for the presidency.
For months, both received prominent, extensive coverage on nightly television newscasts. But after Putin appointed the relatively obscure Viktor Zubkov as prime minister in September, both Ivanov and Medvedev were relegated to relatively brief segments late in the broadcasts.
The conflict between Putin's desire to create a precedent in Russia for the legal handover of power and his apparent conviction that he is the only figure capable of guaranteeing stability has led to months of political confusion and melodrama.
But the question of succession may be approaching a resolution, analysts here say.
Putin has hinted he might become prime minister, or run for president again after leaving office next spring. He has said that a big victory for United Russia, as expected, will give him the "moral authority" to hold the parliament and government accountable for continuing to pursue his policies.
Supporters in and out of the Kremlin meanwhile have talked about making him a "national leader" - though they have not said what formal title he might hold.
Some believe that Putin may still reconsider his decision not to run again.
"Increasingly there is a sense that Putin needs to stay on, among the elites and I think Putin himself," said Lipman.
Although the Kremlin and its allies appear to have stage-managed much of the recent clamor for Putin to stay in power, there is genuine grass-roots support for such a move.
He has quelled a separatist and Islamic rebellion in Chechnya; wrested control of Russia from a small band of billionaires, called oligarchs; and presided over Russia's economic resurrection following its near collapse in the 1990s.
Government salaries and pensions are generally paid on time, unlike a decade ago. Corruption, though worse than ever according to watchdog organizations, receives far less media coverage than it did under the late President Boris Yeltsin.
Critics say Russia would have developed faster economically and politically under more democratic leadership. They warn that the concentration of power in the Kremlin will in the long run weaken the state, by blinding it to social unrest.
Putin has also resurrected many symbols of the Soviet era, from the national anthem to the army's Red Star. He has also revived, to a limited extent, the Soviets' habit of competition and confrontation with the West.
So far, though, he has not launched the kind of massive military buildup needed to make Russia, once again, a major geopolitical power.