Short answers, pulled from the story.
Presidential elections took place in Russia on the 4th of March 2012. This vote marked a significant change because it was the first election held after constitutional amendments introduced in 2008.
The Central Election Commission officially registered Vladimir Zhirinovsky, Gennady Zyuganov, Sergey Mironov, Mikhail Prokhorov, and Vladimir Putin as the five presidential candidates. Vladimir Zhirinovsky represented the Liberal Democratic Party at age 65 while Gennady Zyuganov led the Communist Party at age 67.
Vladimir Putin received 63.6 percent of the vote according to the Central Election Commission of the Russian Federation. Voting abroad showed a different pattern where 73.24 percent went to Putin compared to 13.56 percent for Prokhorov.
International observers from the Organization for Security and Co-operation in Europe found that there were serious problems from the very start of this election including abuse of government resources. The OSCE concluded voting on the day of the election was assessed positively overall but the process deteriorated during the vote count which was assessed negatively in almost one-third of polling stations observed due to procedural irregularities.
Putin was inaugurated in the Kremlin on the 7th of May 2012. Public protests had taken place in Moscow on the 6th of May with an estimated 8,000 to 20,000 protesters taking part before his inauguration.