According to first results, incumbent Serbian president Boris Tadic and ex-nationalist Tomislav Nikolic are likely to face each other in presidential elections runoff, RIA Novosti reported.
Serbia voted in presidential, parliamentary and municipal elections on Monday.
According to the country's election commission's data obtained from 26% of the country's polling stations, Tadic received 24.81 percent of the vote and has a narrow lead over his main election rival, who has 24.71 percent.
Interior Minister Ivica Dacic is third, with 15.76 percent of the vote.
At Serbia's previous presidential elections in 2008, Nikolic led after the first round, but lost 2.3 percent to Tadic in the runoff.
The Center for Free Elections and Democracy (CeSID) said in its early results that Tadic won 26.7 percent, while Nikolic received 25.5 percent of the vote.
The candidates' political parties are also close in parliamentary polls. With 7.5 percent of ballots counted, Tadic's Democratic Party (DS) received 21.3 percent and appears to be narrowly behind Nicolic's Serbian Progressive Party (SNS) (24.2 percent).