Kremlin ally Sergei Sobyanin has won a Moscow mayoral election, according to results released by electoral officials after a complete vote count, but opposition leader Alexei Navalny claimed the results were falsified.
Polling precincts gave Sobyanin, the acting mayor, nearly 51.3 percent, the city electoral commission said early on Monday, enough to clear the 50 percent threshold needed to avoid a second-round runoff.
Navalny, who was second with 27.3 percent, alleged that the vote count was marred by "many serious violations".
He said in a statement: "We consider the official election results to be deliberately falsified."
Navalny, who is a major critic of President Vladimir Putin, insisted he had managed to force the mayor into a second round and threatened street protests if the authorities did not acknowledge that Sobyanin had polled less than 50 percent.
"We demand that a second round is held. If that is not done... we will appeal to the citizens and ask them to take to the streets of Moscow."
Speaking to Al Jazeera from London, Lilit Gevorgyan, an analyst at IHS Global Insight, said it was not surprising that the opposition candidate came in second in Moscow.
"It was expected that Navalny would gather at least some votes, but to expect that the grassroots leader would snatch power in the most important city in Russia was probably unrealistic," Gevorgyan said.
In a late-night rally in central Moscow attended by thousands and lit up by fireworks, Sobyanin had said he was sure of victory and congratulated himself for organising "the most honest and open elections in the history of Moscow".
"We have something to be proud of," he told the cheering supporters.
But turnout was low at 26.5 percent as of 14:00 GMT, an unusually flexible figure, which indicated that Navalny had been far more successful at bringing out his supporters than the mayor, who ran a supremely low-key campaign.
Communist candidate Ivan Melnikov was third in the partial results with just more than 10.6 percent of the vote, while other contenders merely made up the numbers. Muscovites had six candidates to choose from.
The candidacy of Navalny - who campaigned under the shadow of a conviction in a controversial embezzlement case - made the race the first genuinely competitive Russian election since the heady early post-Soviet years.
The election was seen as a crucial test of the protest mood in the city, which was shaken by huge demonstrations against Putin's decade-long rule in the winter of 2011-2012.
"This is a victory for Navalny, the results he's received are very good, even if there will be no run-off," Gleb Pavlovsky, a political analyst and one-time Kremlin consultant, told AFP news agency.
Putin, who made no secret of his support for his former Kremlin chief of staff Sobyanin, said Moscow did not need a politician for a mayor.
"Such big cities do not so much need to be run by politicians," he said after casting his vote in Moscow, adding that uch a city should be managed by "depoliticised people, technocrats".
Al Jazeera’s Peter Sharp, reporting from Moscow, said Navalny had been carrying out the “first-ever Western-style political campaign, using social media and political slogans such as 'change Russia, start with Moscow'".
In July, Navalny was sentenced to five years in a penal colony on fraud charges that he says were trumped up and arrested in court.
A day later he was suddenly released pending his appeal, in an unprecedented move observers say showed that the Kremlin did not know how to handle him.
Sobyanin, appointed to a five-year term by the Kremlin in 2010, had called an early election to bolster legitimacy and strengthen his position.