The Moscow mayoral election is the highest-profile of the votes, but serious opposition candidates have been kept off the ballot paper in favour of incumbent Sergei Sobyanin.
As with the presidential election in March, which saw Vladimir Putin return to the Kremlin for a fourth term with ease, the focus has moved to turnout due to the lack of suspense over results.
Authorities in the capital have organised festivals and food fairs at polling booths to drive up participation and lend legitimacy to Putin ally Sobyanin's next term as mayor.
But opposition leader Alexei Navalny, who is serving a month-long jail term over an earlier illegal protest, is trying to spoil the party with nationwide demonstrations against pension reforms.
"For 18 years, Putin and his government have stolen from the budget and squandered it on meaningless projects. Now the money's run out and we have to steal from pensioners to make ends meet," Navalny's team wrote on social media pages announcing the events.
Dozens of supporters and protest organisers have been held by police ahead of the demonstrations, Russian media reported.
The majority of the protests planned for Sunday have not been sanctioned by authorities, meaning those who turn up could face arrest.
Russians in various regions will be voting for their governors, local lawmakers and other officials.
In Moscow, Sobyanin is expected to be returned to city hall with around 70 per cent of the vote, on turnout of 30 to 40 per cent.
The mayoral election of five years ago was the last time Russian politics came close to a major upset, with Navalny nearly forcing Sobyanin into a runoff.
This time he will face only low-profile candidates from the Communist Party, the nationalist LDPR and two other groups, with more vocal opponents barred under new rules.
"Moscow is a city where a minimum of 30 per cent of people are our potential supporters, they share our ideas," said former opposition MP Dmitry Gudkov, who himself was blocked from the ballot.
But "there's a complete absence of a real opponent... there's no one from the democratic side," he told AFP.
Supporters say Sobyanin has transformed the city with billion-dollar renovation projects that include a showpiece central park and new pedestrian areas along with a string of new metro stations.
But critics argue these are a sop to a new urban middle class which has in the past protested against Putin's rule, as the Kremlin continues to crack down on political freedoms.
Polls open at 8 am with protests called for 2 pm local time.