MOSCOW, Russia — Opposition leaders hope to revive their anti-Kremlin movement after a summer lull by bringing tens of thousands of protesters onto the streets on Saturday in defiance of what they say is a coordinated crackdown on their activities.

The authorities have made overt moves to eject an outspoken lawmaker from parliament; they have charged a key opposition leader with financial crimes; passed laws to restrict protests and summoned opposition lawyers for questioning.

Turnout at the rally will help gauge whether the moves are dampening or reinvigorating discontent centered in large cities that erupted last December and led to clashes with police on the eve of President Vladimir Putin’s inauguration in May.

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“Tightening the screws has the opposite of its intended effect for many and spurs them to attend because it makes them indignant,” said Sergei Mitrokhin, chairman of the opposition Yabloko party.

“It doesn’t necessarily lead to a downward turn,” he added. “Some people probably won’t come, but it’s hard to forecast.”

The mayor’s office on Tuesday granted the opposition permission to hold its protest — which organizers have wishfully dubbed the “March of the Millions” — after ruling out a march down Moscow’s main Tverskaya Street that would have ended with a demonstration by the Kremlin walls.

The rally will mix liberals, nationalists, leftists, anarchists and gay activists. The Communist Party, which has a large electoral base but has so far shied away from joining street protests, will officially attend for the first time.

The Communists also vehemently denounced a move by the ruling United Russia Party to eject lawmaker Gennady Gudkov of the left-leaning Just Russia Party from parliament and strip him of his immunity.

United Russia accuses Gudkov, a former KGB officer who’s a prominent protest supporter, of engaging in business activities forbidden by his parliamentary post. He denies the charge, saying it’s a political reprisal for his outspoken stance.

He and his son Dmitry, also a legislator from Just Russia, have responded by publishing what they say is evidence United Russia is illegally engaged in business.

Gudkov’s fate is set to be decided by a vote on Friday in the 450-seat State Duma, where United Russia holds a slim majority.

Commentator Oleg Kashin of the influential Kommersant daily speculated Gudkov’s two allies from A Just Russia and another outcast from the Communist Party could also soon be expelled from parliament, criticizing the possibility by saying, “Now United Russia itself is the court.”

The two Gudkovs and colleague Ilya Ponomaryov were the main instigators of an unprecedented parliamentary filibuster that failed to derail a bill seen as part of the legislative crackdown on the opposition. Passed in June, it increased fines for protesters deemed to have caused injury to people or damage to property by a factor of more than 120.

The State Duma has since recriminalized slander, required NGOs receiving foreign funding to brand themselves “foreign agents” and passed a bill regulating the internet that prompted criticism from Google and other online giants.

Putin defended the internet law as necessary to protect Russian children in an interview with the Kremlin-funded English-language television channel RT last week.

"So is it true that other countries don’t have laws that ban child pornography, including on the internet?" he asked. “If we talk about what some call a clampdown ... we should clarify what we’re talking about. If we understand it as a simple requirement for everyone, including the opposition, to comply with Russian law, then this requirement will be consistently enforced.”

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The authorities’ crackdown has included charges against Alexei Navalny, a leading opposition figure and anti-corruption campaigner, of embezzling half a million dollars from state coffers. He could face up to 10 years behind bars.

More than 10 activists charged with taking part in mass disturbances during the May protest against Putin’s inauguration remain in jail. Some also reportedly face up to 10 years in prison.

One of them — whose lawyer says he was arrested half an hour before the crime he allegedly committed is said to have taken place — has appealed to the European Court of Human Rights.

Investigators have summoned for questioning at least three other opposition lawyers who defended the Pussy Riot activists sentenced to two years in prison last month about their involvement in the May protest.

A state television report by a journalist well known for scathing attacks against Kremlin critics claimed this week that the exiled tycoon Boris Berezovsky backed the female punk rock group to destabilize society. The program, titled "Provocateurs," said Berezovsky doled out large funds to international celebrities to support the band.

On Wednesday, however, Prime Minister Dmitri Medvedev said the three female group members should be released, in what some believe to be a first move to end a case that has reverberated more than the Kremlin expected.