( dpa ) - Voting started Sunday in a tense presidential election run-off in which Serbia would signal its European course in the next five years.
The 6.7 million registered voters are to choose between the pro-European incumbent Boris Tadic and the ultra-nationalist Tomislav Nikolic.
Tadic, who says that Serbia must remain on its EU-course regardless of Western support of Kosovo's secession, heads the Democratic Party (DS), the senior partner in the cabinet coalition with Prime Minister Vojislav Kostunica's Democratic Party of Serbia.
Nikolic leads the opposition Serbian Radicals, the strongest single party in the country, which was a key part of Slobodan Milosevic's regime until it was toppled in 2000.
As Kostunica, Nikolic says Belgrade should freeze its relations with the West over Kosovo.
He led Tadic in the first-round vote on January 20 by more than 4 per cent, but pollsters estimated that Tadic has a slight advantage in the decisive vote on Sunday.
The difference is however expected to be dramatically slight - some reports said that it could be less than 1 per cent and that the election may be decided by as few as 20,000 votes.
Kostunica refused to back either his uneasy ally Tadic, or the opposition leader Nikolic, with whom he stands closer in views of Serbia's Kosovo ad European policy.
Polling ends at 8 pm local time (1900 GMT). Early results are normally expected within a few hours, but may this time be delayed if the score turns out to be as close as was anticipated.