MOSCOW (AP) — Early results Sunday in Russia's parliamentary election showed the dominant pro-Kremlin party well in the lead, but it was unclear if the party will retain the two-thirds majority of seats that allow it to change the constitution.

The election is widely seen as an important part of Russian President Vladimir Putin’s efforts to cement his grip on power ahead of the 2024 presidential election, in which control of the State Duma, or parliament, will be key.

Results from about 30% of the country’s polling stations gave the pro-Kremlin United Russia party 45% of the vote for the 225 deputies apportioned by party lists, according to the elections commission. Another 225 lawmakers will be chosen by individual races, and the elections commission said early results showed United Russia candidates leading in 179 of those single-constituency seats.

The election Sunday lacked significant opposition presence after Russian authorities declared organizations linked to imprisoned Alexei Navalny, the Kremlin’s most prominent foe, to be extremist. The voting was also marred by numerous reports of violations, including ballot-stuffing.

The early results showed three other parties that almost always support Putin returning to the State Duma, as well as the New People party, which was formed last year and is regarded by many as a Kremlin-sponsored project.

The Communist Party received about 22% of the party-list vote, a sizeable improvement from the 13% it got in the last election in 2016. United Russia got about 54% five years ago, so the early results indicate a substantial falloff in support.

The Communists “are gaining everywhere where they were able to field a strong campaign and that's great. It's not great because we love the Communist Party, because we don't, but because it increases the level of political competition in Russia,” said Leonid Volkov, a top Navalny aide.

Ahead of the election, Putin expressed hope that the United Russia party would retain its dominance in the parliament, where it held 334 seats out of 450. But although the party is Putin’s power base, it is far less popular than the president himself.

The vote this year saw most opposition politicians and activists barred from running as Russian authorities unleashed a massive effort to suppress protests and dissent.

Reports of ballot violations from Russian media, opposition politicians and election observers in the three-day vote have been flowing since Friday morning, when unexpectedly long lines formed at polling stations in Moscow and other cities. Some of those in line told reporters they were forced to vote by their employers, often a state-run institution.

Over the weekend, multiple videos of ballot-stuffing circled on social media. In some regions, incidents of “carousel voting” were reported — groups of voters casting ballots multiple times at different polling stations — as well as clashes between election monitors and poll workers.

Russia's Central Election Commission chief Ella Pamfilova confirmed at least eight incidents of ballot-stuffing in six Russian regions. In all, the commission has so far invalidated 7,465 ballots in 14 regions.

In recent months, authorities have unleashed a sweeping crackdown against opposition politicians and the Smart Voting strategy devised by Navalny to consolidate the protest vote against United Russia. Smart Voting increases opposition candidates' chances of winning by telling voters which candidates in specific areas have the best chances at defeating ones backed by the Kremlin, and the authorities have made numerous attempts to wipe it off the internet.

About 50 websites run by Navalny have been blocked, including the one dedicated to Smart Voting.

On Friday, Apple and Google removed an app which features Smart Voting from its online stores for Russian users under pressure from the authorities. The founder of the messaging app Telegram, Pavel Durov, on Saturday also blocked a chat bot dedicated to Smart Voting. And YouTube blocked access to several videos listing the candidates endorsed by Smart Voting.

Navalny's allies ascribed the crackdown on Smart Voting and the reports of voting violations to the Kremlin's lack of confidence in getting the result it wants.

“Either they're so insecure and fear Smart Voting so much ... or the ratings are even worse than we've seen, or they failed to keep their nerves in check — but the level of blatant falsifications have turned out to be even higher than in 2011,” Navalny's top strategist, Leonid Volkov, wrote on Facebook.

Reports of mass vote rigging in Russia's 2011 parliamentary elected triggered months of anti-government and anti-Putin protests.

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