BELGRADE, Serbia (CNN) -- Serbians have hailed the surprise success of President Boris Tadic's pro-Western party in parliamentary elections as a key step forward along the country's path towards membership of the European Union.
Boris Tadic celebrates victory in Serbia's closely fought election and vows to take his country to Europe.
Tadic claimed an emphatic victory on Sunday night and vowed to form a government as soon as possible as preliminary estimates showed the alliance of parties spearheaded by his Democratic Party on course to claim around 39 percent of the vote.
"Serbian voters have confirmed the clear European path for Serbia," Tadic told cheering supporters in Belgrade. "Serbs want to go down the road to the European Union and Serbia will be in the EU."
The result marked a big setback for Serbia's nationalist alliance between the Radical Party and the Democratic Party of Serbia of former prime minister Vojislav Kostunica, which had hoped to win power on the back of popular resentment towards the West over Kosovo's declaration of independence.
Technically, nationalists could still claim the simple 126-seat parliamentary majority necessary to form a coalition if the hardline Radical Party -- polling around 28 percent of votes -- can strike a deal with Kostunica's Democratic Party of Serbia (11 percent) and the resurgent Socialist Party of Serbia, which appeared set to make its biggest electoral gains since the end of the Slobodan Milosevic era, polling around eight percent of votes.
"We have demonstrated that on the ideological level we can be in a coalition," Radical leader Tomislav Nikolic said of the prospect of forging a coalition with Kostunica. "There will be a Radical, Democratic Party of Serbia and Socialist government or there will be new elections." Watch Tadic declare victory »
But analysts said the vote had given Tadic's party a clear mandate to form the next government, either as a minority administration or in partnership with minor parties. Political leaders have 90 days from the release of official results to agree a coalition. Tadic, who personally spearheaded the Democratic Party's campaign, has yet to nominate a prime ministerial candidate.
"The electorate has voted in favor of Europe and the European future is guaranteed," said Zoran Lucic of Belgrade's Centre for Free Elections and Democracy. "Now we have to wait and see what the politicians will do with this expression of the people's political will."
Serbs flooded onto the streets of Belgrade to celebrate late into Sunday night as preliminary results of the election were announced. Hundreds gathered in a central street, dancing and cheering and waving Serbian and EU flags and letting off flares and firecrackers as fireworks filled the sky overhead.
"We are celebrating because this is the beginning of Serbia's path towards becoming a member of the European Union," 25-year-old computer programmer Marko Cirovic told CNN. "We are here to show the world that young people in Serbia have a future."
Mia Cankovic, a 20-year-old law student at Belgrade University, told CNN that the election proved that Serbian people wanted to be a part of Europe and said she hoped closer ties with the EU would enable her to travel abroad.
"The only way forward is Europe. This result is fantastic because it proves that the Serbian people are smart and clever and thinking about their future," she said.
Marko Pantelic, 20, said the election proved that Serbians were opposed to a return to the muscular nationalism of the 1990s, when the Radical Party had served in government in partnership with former president Slobodan Milosevic.
"The Radicals are stuck in the past," Pantelic told CNN. "They still believe in fighting wars and that's not the way to do things in Europe, that's not the way to live. They want to live inside the walls and I don't want to do that."
While the Democratic Party carries strong support among younger Serbians, many older voters also said they had backed the party.
"I have two daughters and five grandchildren and they realize the importance of our country going into Europe," said Jarko Spasojevic, a 65-year-old retired member of the Yugoslav army from the town of Sabac, outside Belgrade. "I voted for their futures and for the futures of all young people in Serbia as well."
Since coming to power in January's presidential election, Tadic is credited with winning a series of concessions from the EU to bolster support for his party, including the signing in recent weeks of a key pre-membership agreement setting his country on course towards full accession and measures liberalizing the strict visa regime for Serbian citizens wishing to travel to EU countries including neighboring Hungary, Romania and Bulgaria.
Sunday's vote also saw local and parliamentary elections carried out peacefully across Kosovo despite the objections of the region's Albanian leaders and United Nation administrators.
Although he insists that Kosovo is a part of Serbia, Tadic has refused to make that a condition of Serbia continuing along the path towards joining the EU. That has earned him death threats and saw him regularly labeled a "traitor" by Kostunica during campaigning.
Speaking to supporters on Sunday night, Tadic said he would lead the fight to preserve Kosovo. "We will continue to fight that diplomatically," he said.