Opposition supporters holding posters of Barack Obama reading "America We Believe In" at a rally Friday in Tbilisi.
The rally in the capital, Tbilisi, marked the first anniversary of a crackdown on opposition demonstrators, when police fired rubber bullets, tear gas and water cannons to end days of protests outside the parliament.
"We are starting a new wave of civil confrontation, and we will not give up until new elections are called," Kakha Kukava, a leader of the opposition Conservative Party, told the crowd.
Speakers demanded parliamentary and presidential elections in early 2009. They repeated accusations of election fraud.
Analysts and Western diplomats said Saakashvili's popularity appears for now undented, but warned that social discontent could spread as the economic fallout from the lost August war and the global financial crisis kick in. A September poll conducted by the U.S.-based, government-funded International Republican Institute indicated that support for Saakashvili and his government was higher than before the war. A majority of those polled — 52 percent — said they would vote for Saakashvili if elections were held the following Sunday. That figure was up from 34 percent in February.
Voices of discontent have grown louder since the five-day war with Russia, when Moscow sent in tanks and troops to repel a Georgian military bid to retake the country's breakaway region of South Ossetia.
"Saakashvili should step down," said Vakhtang Dolidze, a pensioner. "He was not elected by the people and brought shame on us by losing our territories in war."
Reports by rights groups have undermined Saakashvili's efforts to portray the conflict as purely defensive.
A Nov. 4 report by U.S.-based Human Rights Watch alleged the widespread use of cluster munitions — a widely criticized weapon that disperses smaller bomblets across an area the size of a football field — by Georgia in civilian areas.
Civilian buildings in the South Ossetian capital sustained serious damage despite Georgia's insistence that it did not target them. Buildings were leveled, and a tank round pierced the clearly marked wall of the city's central hospital, scattering debris and charred medical equipment throughout the floor.
The New York Times reported Friday that observers with the Organization for Security and Cooperation in Europe, who were in the area when the war broke out, have given accounts saying they were unable to verify that ethnic Georgian villages were under heavy bombardment in the hours before the Georgian offensive, as Georgia has claimed.
The BBC quoted Ryan Grist, a former senior OSCE monitor in Georgia, stating that Georgia was responsible for "an indiscriminate attack on a civilian town" at the outset of the conflict.
OSCE chairman and Finnish foreign minister Alexander Stubb told the BBC that the 56-nation security organization had failed in its diplomatic efforts to prevent the fighting and there was a "lot of propaganda and allegations" about who started the war but that the situation remained unclear.