Putin, who was Russia's president from 2000 to 2008, is running for a third, now six-year term in a March 4 election. He is expected to win easily against four Kremlin-approved challengers, but an unprecedented wave of protests has undermined his image as a strong leader who rules with broad public support.
Sunday's protest appeared to have drawn close to the 34,000 people that opposition activists estimated were needed to complete the chain along the Garden Ring, a wide road that makes a loop around the city centre. Almost all of the people standing in the wet snow wore the white ribbons that have become a symbol of the peaceful anti-Putin protest movement.
Young Putin supporters also were out on sections of the Garden Ring on Sunday. Wearing heart-shaped red signs around their necks that said "Putin loves everyone," they handed out similar ribbons in imitation of the protesters. Some passers-by refused to take the pro-Putin ribbons, which had stripes of white, blue and red like the national flag.
The Garden Ring was the scene of protests on two previous Sundays, when hundreds of people drove cars decorated with white ribbons and balloons as others waved from the sidewalks and overpasses as they went by, horns blaring.
These demonstrations have helped the protest movement maintain momentum between the huge rallies in Moscow that have drawn tens of thousands of people.
The protests began in December following a parliamentary election that saw widespread vote rigging to boost the results for Putin's party. Many Russians were already steaming over Putin's announcement in September that he and President Dmitry Medvedev intended to swap jobs. The presidential election was presented as a formality.
No longer willing to tolerate Putin's system of "managed democracy," the protesters have demanded fair elections in which opposition candidates are free to take part. Some protesters have called for Putin to step down.
Participants in Sunday's demonstration held up white signs in the shape of a car's license plate that said, "We'll drive out Putin." The number on the plate was 04 03 12, the date of the election.
After the demonstration ended, about 1,000 of the activists moved to a square near the Kremlin where festivities were underway for Maslenitsa, or Butter Week. The holiday, similar to Carnival in the West, precedes Lent in the Orthodox Christian calendar and ushers out the winter.
"We believe that Russia will not withstand six more years of political winter," opposition leader Sergei Udaltsov said. "Everything will freeze completely. Therefore, we have to do everything we can to prevent that."
The protest ended with the activists releasing bunches of white balloons.
