Voters across Russia are set to vote in regional elections on Sunday that are seen as a gauge of public opinion ahead of parliamentary polls next year.
About 59 million people - nearly half the population - are eligible to vote for governors and regional parliaments.
But the main opposition Democratic Coalition has only been allowed to stand in one region, Kostroma.
The coalition includes the parties of murdered politician, Boris Nemtsov, and protest leader, Alexei Navalny.
Navalny cannot run for office as he is serving a suspended prison sentence in an embezzlement case that he argues was fabricated.
The Duma has been stripped of any real opposition under President Vladimir Putin, whose approval rating remains consistently high.
The elections will reveal the mood of Russians after more than a year of financial hardship caused mostly by low oil prices and Western sanctions over Moscow's alleged military role in Ukraine.