The official campaign for snap Moscow mayoral elections started Tuesday with the publication of the City Duma's decision to hold the vote on Sept. 8 in City Hall's official newspaper, Tverskaya 13.
Candidates can submit the paperwork required to register their bids with the elections committee beginning Wednesday, Interfax reported.
Under stringent rules introduced with the return of direct gubernatorial elections last year, all candidates must collect signatures from 6 percent of municipal deputies in at least three-fourths of all local municipalities, or 110 signatures in total.
In addition, independent candidates must collect signatures of support from at least 1 percent of Moscow voters, or 73,021 people.
Candidates have 30 days to register with the elections committee, and the committee will then spend 10 days verifying signatures and other documents.
Moscow's top elections official, Valentin Gorbunov, has said the mayoral election will cost the city budget 430 million rubles ($13.3 million).
Candidates will be allowed to spend 200 million rubles on their bids. Of the campaign war chest, 50 percent of the funds can come from the political party supporting his bid, 3 percent can come from the candidate's own pocket and 3 percent can come from companies and other organizations, Interfax said. Individual donors cannot contribute more than 0.5 percent of the 200 million rubles.
The early vote was called after Mayor Sergei Sobyanin, whose five-year term was to end in 2015, resigned June 5 in an apparent attempt to extend his rule at a time when he faces little opposition. Sobyanin, a close ally of President Vladimir Putin who is serving as acting mayor until the election, has said he intends to run as an independent even though he is a member of the ruling but increasingly unpopular United Russia party.
His possible rivals include Alexei Navalny, the opposition leader who has received a preliminary nomination from the RPR-Parnas party; Yabloko party head Sergei Mitrokhin; Left Front leader Sergei Udaltsov; and billionaire and Civil Platform party head Mikhail Prokhorov and his sister Irina.
The political opposition has complained that they have little time to prepare for the snap election, which the City Duma on Friday decided to schedule for Sept. 8, election day in Russia.