Pro-Western incumbent Boris Tadic won Serbia's presidential election Sunday, edging an ultranationalist ally of former President Slobodan Milosevic by a narrow margin. The state electoral commission and independent vote monitors said that Tadic won about 51 percent, while extreme nationalist Tomislav Nikolic had 47 percent. The remaining ballots were invalid. "Serbia has shown its great democratic potential," Tadic said in his victory speech in downtown Belgrade in front of thousands of cheering supporters. He praising Nikolic for "the number of votes he has won." Nikolic, the pro-Russian challenger, said, "I congratulate him (Tadic) on his victory. ... I will continue to be his tough opposition." Tadic's supporters, waving Serbian, EU and Democratic Party flags and honking car horns, celebrated his victory with fireworks. Tadic's Democratic Party played a key role in the ouster of Milosevic in 2000. The soft-spoken party leader first became the president in 2004, beating Nikolic in another runoff election. Nikolic, deputy leader of the ultranationalist Serbian Radical Party, served as a deputy prime minister during Milosevic's 1998-99 war in Kosovo, when NATO bombed Serbia for 78 days to stop his brutal crackdown against the province's separatists. The province has been run by the United Nations and NATO since the war. Kosovo's ethnic Albanian leaders said they would declare independence days after the Serbian runoff, no matter who wins, and they expect the US and most EU countries to follow up with quick recognition. The outcome of Sunday's runoff indicated that a majority in Serbia wants to continue on its path of pro-Western reform and closer ties with the European Union, instead of heading back to nationalism and isolation. Mladjan Dinkic, the leader of the pro-Western G17 Plus party allied with Tadic, said the victory gave Tadic legitimacy to lead the country toward the EU. "There is no chance any more for anyone to put any obstacles on that road because the citizens gave it the legitimacy," Dinkic said. Nikolic's defeat indicated that Serbians had opted for closer ties with the West instead of getting closer to Russia, which was advocated by the ultranationalist candidate. The European Union was quick to congratulate Tadic. The EU "welcomes the fact that the Serbian people seem to have confirmed their support to the democratic and European course of their country," the bloc's presidency, held by Slovenia, said in a statement. Serbia has a "crucial role to play in the Western Balkans, and the people of Serbia are part of the European family," the statement said, adding, "The EU wishes to deepen its relationship with Serbia and to accelerate its progress toward the EU, including candidate status." The election outcome will alleviate fears in the West that Serbia will react violently to the expected declaration of independence from Kosovo. Both Tadic and Nikolic oppose Kosovo's independence, but Tadic has ruled out the use of force and would likely seek to preserve close ties with the EU and the United States even if they recognize Kosovo statehood. While pledging never to recognize Kosovo independence, Tadic has said there is "no alternative" to EU membership for Serbia and that it is "the only way forward" for the nation.