Mr. Medvedev, an unassuming aide to Mr. Putin who has never before held elected office, portrayed himself during a relatively listless campaign as something of a reformer, vowing to crack down on endemic corruption and promote the rule of law.
He also seemed to take a less strident stance toward the West than Mr. Putin. Mr. Medvedev’s success at adopting this platform early in his tenure will represent an important indicator of whether Mr. Putin will allow him to be more than a figurehead.
Mr. Putin has pledged to serve as Mr. Medvedev’s Prime minister, and he has already indicated that he will broaden the responsibilities of that position, which since the Soviet Union’s fall has typically been administrative.
At a news conference early Monday 3 March morning, Mr. Medvedev offered assurances that he and Mr. Putin would govern Russia well together, saying that they had long known and trusted each other. Their relationship, Mr. Medvedev said, "will become a rather positive factor in the development of our country".
He said he did not envision changes in the structure of the two posts. Asked who would run foreign policy, he said, "That is perhaps the simplest question. Foreign policy, according to the Constitution of the Russian Federation, is determined by the President".
Nonetheless, from the time of the czars, Russia has never had such a joint leadership. Even if Mr. Medvedev and Mr. Putin get along, as they have promised, the very fact that there will be two centers of power could stoke conflicts in a Kremlin that under Mr. Putin has often been the scene of internecine feuding.
"There is much talk about the possibility of big contradictions between the two, but I don’t think there will be any serious ones", said Aleksei Makarkin, an analyst at the Center for Political Technologies, a Moscow think tank. "If there is a confrontation, it could blow up the regime. But it’s not an issue of only the personal relations between the Prime minister and the President, but also the problem of rivalries between the teams around them".
The election of Mr. Medvedev, 42, a first deputy Prime minister, is the culmination of Mr. Putin’s efforts to consolidate control over the government, business and the news media since taking office eight years ago. Vowing to restore stability to Russia after the upheavals of the 1990s, Mr. Putin has increasingly used his authority and popularity to create what is in many respects a one-party State. Mr. Putin, who could not run for a third consecutive term under the Russian Constitution, will leave office with Russia far stronger economically, but also with far less political pluralism.
On Sunday 2 March night, Mr. Medvedev and Mr. Putin celebrated their triumph at an outdoor rock concert on Red Square in Moscow that was attended by thousands of cheering young people and shown on national television. To the kind of rock ballads favored by Mr. Medvedev, the camera followed the two men as they strode across an empty part of the square to the stage, as if they were in a music video.
"Despite this quite unpleasant snow falling from the skies, this is a very special day in the life of our country", declared Mr. Medvedev, who wore a black leather jacket and blue jeans.
The election, he said, "means we will be able to maintain the course suggested by President Putin".
Mr. Putin said, "I thank all our citizens who came to the polls today. It means that we live in a democratic State, and our civil society is becoming efficient, responsible and active".
With about 74 percent of the ballots counted by 2 a.m. local time on Monday 3 March, Mr. Medvedev, of the United Russia Party, had about 69 percent of the vote, followed by Gennadi A. Zyuganov, of the Communist Party, with 18 percent. Vladimir V. Zhirinovsky, an ultranationalist who leads the Liberal Democratic Party, received 10 percent, and Andrei V. Bogdanov, a little-known candidate whose Democratic Party is considered a creation of the Kremlin, had 1 percent.
Officials said turnout was 67 percent.
Mr. Medvedev declined to debate his opponents, and his campaign was conducted largely through staged public events that were widely broadcast on the Kremlin-controlled television networks. His opponents on the ballot received far less coverage.
Throughout the campaign, the Kremlin, having essentially prevented any meaningful opposition, mostly focused on getting enough people to the polls to allow the vote to be depicted as legitimate.
As occurred with the parliamentary election in Russia in December, the leading group of Western election observers refused to monitor the balloting on Sunday, asserting that the Russian government had placed too many restrictions on their work.
Golos, a Russian nonprofit voting-rights watchdog, criticized the voting on Sunday 2 March, saying that it was undemocratic and that in many places, local authorities were exerting pressure on people to vote for Mr. Medvedev.
"There has been intimidation, people have been forced to take absentee ballots and vote at their work places", said Lilia Shibanova, the group’s executive director. "It has been done exactly the same way it was during the parliamentary election. It has already become the norm, unfortunately".
With the election a foregone conclusion, debate has instead revolved around what will be the goals and governing style of Mr. Medvedev, a lawyer who does not have Mr. Putin’s background in the security services.
Andrei A. Piontkovsky, a prominent political commentator and Putin critic, said it was obvious that Mr. Putin chose Mr. Medvedev for his fealty, and little else.
"He is chemically conditioned to obey Mr. Putin", Mr. Piontkovsky said. "This artificial construction of two czars creates a real factor of instability. But Putin is a clever guy, he chooses the person with minimal potential damage for him. It’s also a classic good cop, bad cop structure, with Mr. Medvedev playing the ceremonial good cop role for the West and the Russian intelligentsia".
© The New York Times - Clifford J. LEVY