According to preliminary results based on 82% of the votes counted, Vetevendosje (Self-determination) won 26% of the votes, while another opposition party - the centre-right Democratic League of Kosovo (LDK) - won 25% of the votes.
The leftist Self-Determination Movement led by Albin Kurti and the center-right Democratic League of Kosovo led by former Kosovar prime minister Isa Mustafa took 26 percent and 25 percent of the vote respectively, nearly complete results showed.
The Democratic Party of Kosovo (PDK) was in third place with 22 percent of the vote.
For all that Kosovo has gained since independence - it is now recognized as an independent nation by more than 100 countries - the territory remains in limbo, unable to reach a lasting peace with Serbia, even as its own government is plagued by corruption.
The talks stalled past year after Haradinaj set a 100% tariff on Serb goods.
Kurti has always been an insurgent force in Kosovo politics, railing against the ex-guerillas who have dominated the former Serbian province since independence in 2008.
If the dialogue with Belgrade does resume, one of the most sensitive issues will be settling what powers to grant administrations in Serb-majority parts of Kosovo.
It was Mr Haradinaj's resignation in July - after being called to The Hague for questioning as a suspect over his role in the 1998-99 insurgency against Serbia - that sparked the snap election.
Speaking in Belgrade, Serbian President Aleksandar Vucic said he would be ready to talk to Kurti's party if they are deemed the "legitimate representatives" of Kosovo.
However, for many of Kosovo's 1.8 million citizens, high unemployment, widespread corruption and poor healthcare are more pressing concerns than the talks.
In 2013, Pristina and Belgrade consented to an EU-mediated conversation to normalize ties, but little progress was made.
The ruling Democratic Party (PDK) of President Hashim Thaci came closely behind at 21.7 percent.
In Kosovo, all three parties LDK, Vetevendosje and PDK said the land swap was not acceptable.
The Vetevendosje leader and candidate for prime minister, Albin Kurti, said that as of Monday he will start efforts to form the new government.
Kosovo has Europe's youngest inhabitants, with a mean age of 29, and has witnessed annual economic growth averaging 4 percent within the last ten years, but it stays weak.
The future government needs to be endorsed by at least 61 members of Kosovo's 120-seat parliament.
The general public sector is the largest employer in the nation, but a candidate usually wants political relations or to pay a bribe to discover work.
The message from the election was very clear, however, he said.
"If you have money you can buy justice here, if you have money you can buy health because you go to a private clinic. My vote is the only thing I have", said Qendrim Agushi, 32, a construction worker who earns 13 euros a day.