MOSCOW (AP) -- Two exit polls in Moscow's mayoral election predicted a strong showing Sunday for opposition leader Alexei Navalny, putting him behind the Kremlin-backed incumbent but with the race far closer than expected.
But as election results began to trickle out more than two hours after polls closed, showing incumbent Sergei Sobyanin with a clear majority, Navalny said the slowness in reporting the results and the lack of an official turnout figure raised suspicions that the vote was being manipulated.
"We don't recognize the results that are currently being announced, and I would like to say that we won't give up one vote that we received," Navalny told reporters at his campaign headquarters. "I call on the Kremlin and the mayor's office to restrain themselves from falsifications."
The election has energized Russia's small opposition in ways that could pose a risk to the Kremlin in the days and years ahead.
It also could determine Navalny's fate. He faces time in prison after being convicted of embezzlement in a case seen as part of a Kremlin effort to sideline him, but a strong showing could lead to a shortening of his five-year sentence, if the Kremlin felt this would help defuse discontent.
The exit polls by pollsters FOM and VTsIOM, which are both usually seen as favoring Kremlin candidates, put incumbent Sergei Sobyanin in the lead with about 53 percent.
FOM predicted Navalny would get 29 percent, while VTsIOM showed him even higher, at 32 percent. This is far more than expected. A week before the election, a poll by the independent Levada Center predicted Navalny would get 18 percent, compared to 58 percent for Sobyanin. Four other candidates trailed far behind.
With less than 4 percent of the vote counted, the Central Election Commission said Sobyanin was leading with 57 percent and Navalny had only 22 percent.
Getting above 50 percent would allow Sobyanin to avoid a runoff, but if he is seen as squeaking through unfairly because of vote-rigging, it could set off protests. It was reports of widespread fraud in a national parliamentary election in 2011 that triggered the unprecedented demonstrations against President Vladimir Putin's rule.
Navalny's campaign said its own exit polls showed Sobyanin below 50 percent.
Arriving at his local polling station early on Sunday with his wife and children, Navalny said he hoped there would be no vote-rigging at the polls so that voters could choose "the political space they need for a new Moscow."
Golos, Russia's leading independent election monitor, said the voting appeared to have gone smoothly, but there were fears that election officials would artificially increase the turnout to allow them to add votes for Sobyanin.
"This is the dilemma: Either they manipulate something somehow, but then they could be caught and won't be able to sleep soundly on Monday," Golos co-chairman Grigory Melkonyants said. "Or they could let it be a real election and allow a second round."
Golos observers noted that voter rolls at some polling stations had been padded with people who no longer lived in the neighborhood. They also noted that many people coming to the polls who receive benefits or salaries from the state had been pressured to do so. One woman demanded a document stating that she had voted, supposedly as proof for the state hospital where she worked, the group said.
Anna Grishina, a retiree who came out of the polling station soon after Navalny, clutched her cane and said proudly that she'd voted for Sobyanin.
"I don't see them," she said, when asked about which changes Sobyanin had brought to the city. "But I hear about them on TV. He's opened new metro stations and redone the roads. I can't remember all of the things right now."
The majority of people at the polls early in the day appeared to be elderly, a group that makes up Sobyanin's core group of supporters. But Alexei Gorshkov, a 34-year-old employee in the IT sector who voted for Navalny, said he hoped the younger voters just hadn't woken up yet.
"Sobyanin and Putin spend most of their time lining their own pockets," said Gorshkov. "It doesn't matter who you vote for today, as long as you vote against Sobyanin. If there's a run-off, Navalny will have a real chance."
Navalny had built an online following through his anti-corruption blog, but it was the protests of 2011 and 2012 that cemented his status as de facto leader of the opposition. He led street marches that attracted tens of thousands of people from across the political spectrum.
His mayoral candidacy inspired a grassroots campaign like nothing the city had ever seen before. About 20,000 volunteers hit the campaign trail for Navalny, passing out leaflets in the metro or hanging banners on balconies. Navalny held impromptu campaign rallies outside subway stations several times a day.
Sobyanin did not actively campaign, preferring instead to play the regal incumbent and let his work as mayor speak for itself. Putin's deputy since 2005, Sobyanin was appointed Moscow's mayor in 2010.
Sunday's mayoral election was the first since 2003 and the first since the Kremlin last year reversed Putin's 2004 decree abolishing direct elections for the Moscow mayor and other regional leaders.
Since Putin returned to the presidency for a third term, the Kremlin has cracked down on the opposition and tried to stifle dissent.
Navalny was sentenced in July to five years in prison for embezzlement in a case that he and his supporters describe as legally dubious and punishment for his exposure of high-level corruption. He left the courtroom in handcuffs, but a day later in a surprise turnaround, prosecutors requested he be set free until his appeal could be heard.
Most have speculated that it was Sobyanin who had Navalny set free, in order to ensure that the election would look as fair as possible and legitimize the Kremlin candidate as a politician.