By Aleksandar Vasovic and Matt Robinson
BELGRADE (Reuters) - Opposition populists once allied with Serbian strongman Slobodan Milosevic pushed for power on Sunday, buoyed by voter anger over the state of the economy and pledging support for the ex-Yugoslav republic's bid to join the European Union.
Liberals who took power with Milosevic's ouster in 2000 face their strongest challenge yet from the Serbian Progressive Party led by Tomislav Nikolic, once demonized by the West as Milosevic's spiritual heir but who says he now shares the goal of taking Serbia into the EU.
The elections for president and parliament are too close to call. But they have already confirmed an emerging pro-European consensus in a country that since Milosevic has teetered between pro-Western reformers and unrepentant, pro-Russian nationalists.
"Serbia is ripe for change," said Nikolic, 60, who is neck-and-neck in opinion polls with incumbent Boris Tadic in the race for president. "I'm sure the people will send the message that they grasp the gravity of the situation," he said after voting.
"The European Union is our goal. We want the EU if the EU wants us."
Nikolic, a somber former cemetery manager and leader of the populist right, voted among the grey Socialist-era tower blocks of Novi Beograd (New Belgrade).
Tadic, Serbian president since 2004 and leader of the dominant Democratic Party, strolled in trademark open-neck shirt to vote in the heart of Belgrade's upmarket old town.
"Recall the atmosphere of four years ago, or eight, or 12 years ago when it was a question of life and death," the sporty 54-year-old told reporters. "It shows how much a country can change."
Under the Democratic Party, Serbia closed a dark chapter with the arrest and extradition of Bosnian Serb genocide suspects Radovan Karadzic and Ratko Mladic, and in March became an official candidate for EU membership.
But voters look set to punish the party for an economic downturn that has driven unemployment to 24 percent and weakened the dinar. The average Serb takes home 380 euros per month.
Fellow ex-Yugoslav republic Croatia joins the EU next year, driving home for many Serbs just how far they have fallen behind. The Democratic Party has also been dogged by a widely-held perception of elitism after more than a decade in power.
"The Democrats had their chance and they failed miserably so now it's time for a change," said 59-year-old Belgrade nurse Olga Nikolic, who voted for the opposition.
Turnout at 2 p.m. (midday GMT) was 31 percent, slightly higher than in the last elections in 2008.
The Progressives were ahead in polls before the vote, but no party will win an outright majority. Most analysts predict the Democratic Party will retain power with a rehashed version of the outgoing government, an unwieldy multi-party alliance.
Under the constitution, the prime minister is more powerful than the president.
The Socialist Party of Milosevic, who died in 2006, is polling third in the parliamentary election and likely to emerge as kingmaker. Party leader Ivica Dacic has indicated he favors a fresh coalition with the Democratic Party, but might demand the post of prime minister in exchange for his support.
The presidential election will go to a second round on May 20, when most analysts say unease over Nikolic's hardline nationalist past could drive undecided voters into the arms of Tadic.
Nikolic is the former deputy leader of the ultranationalist Radical Party, whose leader Vojislav Seselj is standing trial in The Hague accused of recruiting and financing Serb paramilitaries during Yugoslavia's bloody collapse.
The Radicals were ideological allies of Milosevic, in power with him when NATO bombed Serbia in 1999 to halt the mass killings and expulsion of ethnic Albanians from Kosovo. Nikolic broke away in 2008 when the party split over EU integration.
Tadic, a psychologist by profession, says the makeover is cosmetic. Democratic Party campaign videos have warned Serbs that to vote for Nikolic would be to "gamble with Serbia's European future."
The EU is weighing up whether to open accession talks next year. They could last until 2020.
"Everyone promised the same, so what difference does it make?" said 70-year-old Belgrade pensioner Veselin Rakovac. "I voted for Tadic purely out of habit."
The next government will be pressed to reform the judiciary and pension system, cull the public sector and tackle crime and corruption. Western diplomats concede deep uncertainty over the substance of Nikolic's policy or the capacity of his untested party to overhaul the country.
The EU also wants Serbia to loosen its grip on a northern slice of its former Kosovo province, which declared independence in 2008 but is locked in a de facto partition between the Albanian majority and 50,000 Serbs in the Belgrade-backed north.
NATO bolstered its Kosovo peacekeeping force with 700 extra German and Austrian soldiers ahead of the elections.
Some 6.7 million people are eligible to vote. Polling stations close at 8 p.m. and unofficial preliminary results are expected two hours later.
(Additional reporting by Zoran Radosavljevic in Belgrade and Branislav Krstic in Mitrovica; Writing by Matt Robinson Editing by Maria Golovnina)