MOSCOW -- The ruling United Russia party has dominated a slew of regional and local elections marked by low turnout and claims of voter suppression, but liberal opposition candidates appeared to gain a toehold in Moscow with a strong showing in races for district councils in the capital.

The September 10 elections, the last major vote before a presidential ballot in March 2018, cemented President Vladimir Putin's grip on power in Russia's far-flung regions and tested a new strategy -- at least in Moscow -- for opponents sidelined after years of increasing Kremlin control over the political system.

Nearly complete official counts indicated that United Russia candidates and Kremlin allies, many of them incumbents, won all 15 regional gubernatorial races -- from the Baltic Sea exclave of Kaliningrad to Buryatia on Lake Baikal -- as well as a vote for the head of the naval port city of Sevastopol on Crimea, the Black Sea peninsula that Russia occupied and seized from Ukraine in 2014. United Russia also appeared set to maintain control over regional and local legislatures across the country.

But opposition leaders, including prominent Kremlin critics, claimed victory in several Moscow districts, including Putin's own voting precinct southwest of the Kremlin. The newspaper Novaya Gazeta reported that opposition candidates were on track to win a majority of seats in 14 of the more than 100 administrative districts of the capital.

Partial returns indicated that nearly 180 candidates supported by liberal former Russian parliament deputy Dmitry Gudkov and the Yabloko party won seats in Moscow district councils, and opposition activist Ilya Yashin said he and his allies won seven seats in one of the councils while United Russia won three.

Moscow election commission chairman Valentin Gorbunov said preliminary results with nearly 100 percent of the ballots counted indicated that United Russia won about 77 percent of the 1,502 district council seats being contested in the capital, while Yabloko could win nearly 12 percent and independent candidates about 7 percent.

"Muscovites' political preferences are changing," he said.

Gorbunov said Yabloko was on track to gain 176 or 177 local council mandates, up from the current 25.

Pushed out of national politics since Putin came to power in 2000 and tightened control over elections, opposition activists and groups such as Gudkov, Yashin, and the Yabloko party are focusing on municipal issues and mounting a grassroots campaign to their way claw back. In Moscow, they have their eye on a mayoral election due in September 2018.

Yabloko party official Nikolai Rybakov hailed the results as a breakthrough for the party, adding that Yabloko would attempt to field a candidate for the Moscow mayoral election set for September 2018.

Gudkov told a Moscow press conference that he is in talks with Yabloko to represent the party in that election.

In addition, he said the results send "a very important signal" for the presidential campaign of Yabloko founder Grigory Yavlinsky.

Putin's spokesman said the Kremlin welcomed the fact that candidates who were not from United Russia won seats, casting it as evidence of political pluralism and a fair, competitive vote.

"This is excellent. They will take part in the life of the city and demonstrate their effectiveness," Dmitry Peskov told reporters. "This is pluralism, this is political competition."

Peskov also said "the legitimacy of the elections was ensured in the country on a fairly high level."

Kremlin opponents saw it differently, saying they made progress in the face of alleged fraud and a state campaign to suppress voter turnout in Moscow, where liberal opposition to the Kremlin is stronger than in most other parts of the country.

Gudkov tweeted about what he called an opposition "victory" and Putin foe Mikhail Khodorkovsky congratulated the former lower-parliament-house member and his allies, saying on Twitter that "in the face of United Russia's manipulations, Muscovites have supported a new power."

But the projected opposition wins in Moscow were exceptions in elections in which the newspaper Vedomosti said that "representatives of the party of power won almost everywhere."

"We can speak of the supremacy of and support for United Russia candidates," Peskov said, adding that the results also showed a "quite impressive" level of trust among voters in "officials promoted by the president."

United Russia won a supermajority in the State Duma in elections held last year.

Officials said the incumbent head of the Buryatia region, Aleksei Tsydenov, was on track to win more that 87 percent of the vote. Thousands of kilometers to the west, in Kaliningrad, regional election officials said acting governor and United Russia candidate Anton Alikhanov won 81 percent of the vote.

Kremlin critics say that particularly in the provinces, Putin's government uses a range of tools including control over broadcast media, laws discouraging street protests, and influence over groups such as state employees, soldiers, schoolteachers, and students to improve the chances of United Russia candidates and keep opposition votes to a minimum.

The election came six months before a March 2018 vote in which Putin, who has been president or prime minister for 18 years, is widely expected to seek -- and, given his popularity and control over the levers of power -- easily win a new six-year term.

Putin, 64, would be barred from running again in 2024 because of a constitutional limit of two consecutive presidential terms.

Voter turnout in the September 10 elections was a "record low," the Russian newspaper Vedomosti reported.

Citing official figures, it said turnout exceeded 40 percent in only three regions -- Mordovia, Saratov, and Belgorod -- and was 12.7 percent in the Pacific coast city of Vladivostok.

Gorbunov, the Moscow election commission chief, said on September 11 that turnout was about 14.8 percent "so far," without clarifying whether that was a final figure.

Opposition candidates in the capital had warned that authorities were attempting to discourage voter turnout, and Gudkov and others peppered social media with allegations of fraud in the vote count.

By midday on September 11, the independent Russian election-monitoring group Golos (Voice/Vote) said it had received about 1,600 reports of alleged violations connected to the campaign, voting on Election Day, and the ballot counts.

Sergei Mitrokhin, a representative of the liberal Yabloko party, accused officials of using "every means of giving people a sense of electoral powerlessness...to make sure that the people they need stay in power," the AFP news agency reported.

In a marked shift from previous practice, there were few billboards or posters urging Muscovites to vote, and opposition politicians said there was little information available from the authorities on where and how to cast ballots.

Prominent opposition leader Aleksei Navalny also alleged fraud on the part of the authorities.

Moscow city officials denied charges they were attempting to discourage people from showing up for the election.

WATCH: Vladimir Putin Votes in Russian Local, Regional Elections

Prime Minister Dmitry Medvedev, chairman of United Russia, said the elections were held at the highest level "everywhere" and that the results were "very favorable" for his party, according to state-run media.

Preliminary results indicated a strong performance for parties linked to United Russia, which is associated with Putin.

The opposition had been hoping for a strong showing, especially in Moscow, and to gain some positions in the local elections throughout the country.

Direct governors' races were held in 16 of Russia's 83 regions, and complaints surfaced ahead of the elections from would-be candidates saying they had been unfairly excluded from the ballot.

In nine of the 16 regions with gubernatorial voting on September 10, United Russia's incumbent governors ran for reelection. A second round of voting is scheduled for September 24 in places where no candidate wins a majority.

A requirement is being blamed by some for unduly narrowing the field of candidates for governor. To get on the ballot, would-be candidates must get signatures of support from as high as 10 percent of local lawmakers, the so-called "municipal filter."

In most cases, such local legislatures are either members or allies of United Russia.

At least four potentially formidable candidates had their bids quashed after they failed to secure the required signatures.

Yevgeny Roizman, a Yekaterinburg mayor with a reputation for being a political maverick, failed to get on the gubernatorial ballot in his native Sverdlovsk region. In an interview with RFE/RL's Russian Service in August, Roizman alleged that local authorities made sure "they cleared the entire field."

"There's not a single strong challenger," Roizman said of the process. "Not a single strong candidate was even allowed to get close." Roizman predicted that he would have won "plain and simple" if he had been in the race.

Ella Pamfilova, the head of Russia's Central Election Commission, rejected suggestions that Roizman had been unfairly targeted by the Kremlin.

"It's difficult for me to believe that the ruthless Mr. Roizman -- a senior official, a statesman, the head of a major city who has certain administrative resources -- is a sort of weak little victim hounded by the regime," Pamfilova told the Russian business daily RBK in August.

Ukraine sharply criticized Russia for holding elections in Crimea, which Moscow seized in March 2014 after sending in troops and staging a referendum deemed illegitimate by at least 100 countries.

"Ukraine does not recognize any 'electoral processes' in occupied Crimea, Ukrainian Foreign Ministry spokeswoman Mariana Betsa wrote on Twitter. "A gross violation by Russia of international law and the laws of Ukraine."

"Not worthy of substance and content," she said in a separate tweet.

The European Union also said it does not recognize the elections as legitimate because Russia illegally took possession of Crimea.

"Anybody elected in the Crimean peninsula claiming to 'represent' Crimea and Sevastopol will not be recognized as representatives of those territories, which are Ukrainian," an EU spokeperson said in a statement.

"The European Union remains unwavering in its support for the territorial integrity and sovereignty of Ukraine."

But analysts say the choices were limited, which they said would likely lead to the lower voter turnout.

"There won't be any surprises in the regions because everything is under control," Dmitry Oreshkin, director of the Mercator think tank in Moscow, told RFE/RL.

Oreshkin predicted that United Russia or "people approved by United Russia," would emerge victorious in regional races.

Although he has not officially announced his candidacy, Putin is expected to dominate the presidential election slated for March 2018. It would be his fourth term in the presidency, a tenure dating back to late 1999 and interrupted only by a four-year stint as prime minister to avoid a presidential term limit in Russia's constitution.

With reporting by AP, Reuters, AFP, Interfax, and TASS