Preliminary results have confirmed that the centre-right Slovenian Democratic Party (SDS) received the most votes in Sunday's parliamentary election.
State Election Commission said the party of former prime minister Janez Jansa was in first place with around 25% of the vote after counting three-quarters of the ballots.
However, the SDS may struggle to pull together a government as its hardline stance on immigration has left is short of potential coalition partners.
The next closest party, the List of Marjan Sarec, had about 12%.
The Social Democrats are coming in third place with about 10% while the Left party and the Modern Center Party of outgoing Prime Minister Miro Cerar received about 9%.
Former Prime Minister Janez Jansa tweeted Sunday after the exit poll: “We do not fear tomorrow; we are looking forward to it.”
Jansa, an ally of Hungary's Viktor Orban, said: “If SDS forms the government, we will lead it in a fair way, to the benefit of all citizens.”
The official returns suggest that none of the parties will have a majority in parliament and that negotiations on forming a coalition government are likely to take place after Sunday.
Jansa, who served as prime minister from 2004 to 2008 and 2012-2013 said at a press conference that his party is ready for post-election talks with other parliamentary parties.
The leader of the second-placed party, Marjan Sarec, has ruled out a coalition with Jansa.
A government led by Jansa would shift Slovenia to the right and add an anti-immigration voice to the European Union.
Elections officially sparked by the resignation of Prime Minister Miro Cerar in March but a vote was due to take place this year regardless.