With Russian President Vladimir Putin guaranteed to win another term, authorities are conducting get-out-the-vote efforts to ensure a good turnout.
Associated Press writer Angela Charlton in Moscow contributed.
Polling at around 70 per cent, the macho leader is sure to extend his term to 2024 despite a lacklustre campaign and his refusal to participate in televised debates. "They think of it as a vote of confidence (in Putin)". Sunday's election is expected to further embolden the Russian president both at home and in world affairs.
"The program that I propose for the country is the right one", he said.
Yevgeny, a 43-year-old mechanic voting in central Moscow, said he briefly wondered whether it was worth voting. Detectives are keeping an "open mind" about the death, police said.
He spoke on condition of anonymity because he fears repercussions from his employers if he speaks publicly about the electoral pressure.
Anastasia Arslanova, a 35-year-old lawyer from Sevastopol, said life has become more expensive but that it is a price she is willing to pay to be part of Russian Federation.
"Russia had nothing to do with it", Chizhov told the BBC.
In Moscow, first-time voters will be given free tickets for pop concerts featuring some of Russia's most popular artists who have campaigned for Putin.
Despite the genuine popularity of Putin, the Russian election has been denounced by many as fraudulent and accused the country's powerful leader of using intimidation measures to minimise opposition.More news: Russian Federation expels 23 British diplomats as toxin-attack crisis deepens
Voters were casting ballots across the world's largest country, from the Pacific coast to Siberia and Moscow.
He'll win the election, that's inevitable, but there remains a fierce fight over turnout.
Putin's opponents alleged officials were trying to inflate the turnout. Observers are focusing on whether the Kremlin's overall turnout will bring support to Putin.
Alexei Navalny, who was previously seen as the biggest threat to Putin, has been barred from standing for President because of corruption charges.
Russians in Crimea will be able to vote on Sunday, which coincides with the fourth anniversary of the peninsula's annexation by Moscow.
He also opened a new "international" airport which is part of the moves to counter Crimea's isolation, despite no flights from outside Russian Federation flying to the disputed peninsula.
Russians go to the polls in Ulyanovsk, where Lenin was born. "That's Putin's main quality - he is at the core of our state".
Yekaterina said she wasn't sure what she would do with her ballot, musing that "maybe I'll just write 'Putin is a moron.'" But she understood that not showing up at the polling place Sunday would not only endanger her job but would reflect badly on her boss, whom she likes. But it will take more than action in London to stop Putin.
He is standing against seven other candidates, including millionaire communist Pavel Grudinin and former reality TV host Ksenia Sobchak, but none are polling more than eight percent.
Vladislav Ganzhara, who was seven years old and a Ukrainian citizen when Mr Putin first came to power in Russian Federation, is now a Kremlin-loyal MP in the Crimean parliament. The Kremlin and election officials say any fraud will be stamped out.