By Gabriela Baczynska and Maria Tsvetkova
KHIMKI/BRYANSK, Russia (Reuters) - Russia held local elections from the Baltic Sea to the Chinese border on Sunday, testing President Vladimir Putin's popularity five months into his new term.
The ruling United Russia party was expected to win most of nearly 5,000 contests despite disaffection that cost it dozens of national parliament seats in a December vote and helped spark the biggest opposition protests of Putin's 12-year rule.
Opponents accused the Kremlin of using its position to give favored candidates an unfair advantage by removing potential competitors from races and pressuring state employees. It also alleged violations including multiple voting.
The votes included ballots for regional governors in five of Russia's 83 provinces, the first since the Kremlin restored popular elections of regional chiefs, which Putin had scrapped as he tightened control during his 2000-2008 presidency.
In one example cited by Putin's critics as suspicious, a candidate who had posed a threat to the Kremlin's man withdrew last month from the governorship election in Ryazan province, southeast of Moscow.
Kremlin candidates faced a smooth ride in most other regions electing governors, but in the western Bryansk region longtime governor Nikolai Denin, who was struck from the ballot by a court but reinstated days before the vote, faced a tougher race.
One medical worker in Bryansk accused bosses at her clinic of threatening senior staff with dismissal if they did not vote for Denin at multiple polling stations and record the evidence on their mobile phone cameras.
"I refused, of course," said Maria Makarova, 55, who said she voted for the Communist candidate, Vadim Potomsky.
"What has Denin done in eight years? I get a miserly wage and have to work around the clock to make 6,000 roubles ($190) a month," she said. "He is all talk, and everybody's in poverty."
But Alla, a 72-year-old pensioner who refused to give her last name, said she had voted for Denin. "He did a good thing for my daughter. She has worked in a kindergarten for 25 years and he gave her a good bonus just recently."
A regional election official said the commission had received no formal complaints of pressure on state workers to vote for Denin. The governor's spokesman, Dmitry Ognev, called the claims a "provocation" and said the allegations would be checked.
Among other closely watched votes were the only two contested by prominent leaders of anti-Putin opposition protests: activist and environmental campaigner Yevgeniya Chirikova and liberal politician Vladimir Ryzhkov.
Chirikova cried foul in the Moscow suburb of Khimki, saying hundreds of new residents had been registered in one apartment block alone shortly before the election and accused officials at some polling stations of hiding voter lists from observers.
"New residents were registered early this morning, somehow they received local registration overnight," she said at a polling station. Opinion polls gave her little chance against the United Russia-backed candidate for mayor, Oleg Shakhov.
The regional election commission chief dismissed Chirikova's allegations and Shakhov, the acting mayor, said she should "learn to lose gracefully ... at the polling places I've visited everything is going very calmly and in line with the law."
In the capital of the Altai region, Barnaul, where Ryzhkov was standing, Kremlin opponents said they suspected many people were voting at multiple polling stations and that voter rolls had been illegally inflated to ensure more support for United Russia.
Central Election Commission head Vladimir Churov ordered officials to look into the accusations.
Demonstrations against Putin, which drew as many as 100,000 protesters into Moscow's streets at their height, were sparked by suspicions of fraud in favor of United Russia in the December parliamentary election.
But while the protests exposed dismay among the middle class in Moscow over Putin's return to the presidency after four years as prime minister, the protest movement made few inroads deep in the provinces.
In response to the protests, the Kremlin eased restrictions that had made it very hard for political parties to officially register and contest elections, a change that means more parties were running on Sunday.
But opposition groups say they were kept off many ballots by electoral commissions that often cite minor procedural issues.
More than half the would-be candidates from the liberal People's Freedom Party were kept off or removed from ballots in first-past-the-post races nationwide, the independent vote monitoring group Golos said. ($1 = 31.0190 Russian roubles)
(Writing by Steve Gutterman; Editing by Jon Hemming)