(AP) MOSCOW - More than 20,000 protesters flocked to a central Moscow avenue Saturday to demand Vladimir Putin's resignation and protest electoral fraud, but the crowd's relatively small size compared to recent protests suggested the country's opposition movement has lost some momentum.
Putin, who was Russia's president from 2000-2008 before switching to the prime minister's office due to term limits, won 64 percent of the vote in Sunday's presidential election. Because of changes in the length of the presidential term, he is set to return to the Kremlin for at least 6 years.
His decision to return to the presidency infuriated opposition activists who have grown tired of his heavy-handed rule. A December parliamentary election that was marred by fraud angered many ordinary Russians and bolstered opposition ranks.
Protests held after December's vote attracted up to 100,000 people in the largest discontent in Russia's post-Soviet history. On Saturday, the smaller crowd, surrounded by hundreds of troops and security forces, chanted: "We are the power!"
Although violations at the presidential vote were numerous, observers have viewed the vote as fairer than December's.
But protesters said they do not recognize the vote's results. "These weren't elections. This isn't a president," read a banner.
Opposition leader Garry Kasparov echoed that sentiment from the stage
"This was not an election," said Kasparov, a former chess grandmaster. "This was a special operation from a thug who wanted to return to the Kremlin."
Russian actor Maksim Vitorgan, who was among thousands of independent observers to have volunteered to monitor the presidential vote, said "an amusement park would envy" the large-scale fraud he witnessed.
"We are all humiliated and insulted here," Vitorgan said. Putin "won the war for numbers. He's a president of numbers, not of the people."
"We know the truth, but what are we supposed to do with it?" Vitorgan added, voicing widespread concern that the opposition movement is losing its voice.
Other protesters, however, remained optimistic despite the fact that Saturday's turnout could not match the massive rallies in December and February.
City authorities had given permission for a rally of up to 50,000 on the sidewalk of the central Novy Arbat avenue, which is part of the route used by high-speed motorcades that whisk top figures to and from the Kremlin.
Mikhail Solontsev, a 19-year-old student, who has rallied at opposition protests since December, said the pressure on Putin is already high, and it's up to people to increase it. "It depends on us whether he will step down or not, but he's already scared of us," Solontsev said.
On Monday, the day after the election, Moscow police arrested some 250 people who stayed on a central-city square after the time authorized for a protest rally ran out.
Sergei Udaltsov, leader of the Left Front movement, confirmed Saturday that he was going to try and stay on the street again this time.
"We must do our best so that the Kremlin will be free of the impostor before May 7," he said from the stage, referring to Putin's scheduled inauguration.