Kiev, Ukraine ? Tens of thousands Ukrainians jammed into their capital’s main plaza Monday to protest the apparent victory of the country’s Kremlin-backed prime minister in this weekend’s presidential election, a contest roundly condemned by Western observers as rigged by Ukrainian authorities.

Enduring bitter cold and standing shoulder-to-shoulder for hours in Independence Plaza, throngs of Ukrainians embarked on what appeared to be a burgeoning, emotional rebellion against an election tainted by what election observers called blatant vote-rigging and government bias aimed at handing Prime Minister Viktor Yanukovych the presidency.

Rally organizers began erecting rows of tents for protesters on Kiev’s main downtown street and called for Ukrainians to take part in general strikes across the country.

They also had begun rallying support from Ukraine’s armed forces and police, a tactic that could become crucial if the Ukrainian government resorts to force to crush the movement.

However, many Ukrainians amassed in the plaza said use of force would not break their resolve. Shivering in a forest green, hooded overcoat amid throngs of Ukrainians, 41-year-old accountant Olga Homenka doubted the sight of riot police and tanks would daunt her.

“I’m willing to stand up to whatever force they put up, because as it stands right now, there’s no way back,” said Homenka, her face crimson from a bracing wind. “I feel that if we do not do this now, we’ll never have another chance.”

The nation’s Central Election Commission stopped short of declaring Yanukovych the winner and said the official outcome of the election may not be determined for a couple of days. However, with 99.7 percent of the vote counted, election officials said Yanukovych had garnered 49 percent of the vote, while his opponent, Western-leaning reformer Viktor Yushchenko, had 46 percent. The remaining votes were cast against all candidates, an option allowed under Ukrainian law.