A pro-Russia party looks to have won the most votes in Latvia following Saturday’s general election.
An exit poll put the Harmony party on 19.4% with the pro-EU For Development party taking 13.4% and the right-wing National Alliance on 12.6%.
Other parties have previously formed coalitions to keep Harmony out of government.
However, commentators say it might now be able to form a government if it joins forces with populist parties.
“No coalition combination is possible without Harmony that would appear able and stable,” Nils Ushakovs, Harmony chairman and mayor of the capital Riga told the Leta news agency.
Prime Minister Maris Kucinskis’s governing coalition comprising the Union of Greens and Farmers; the National Alliance and the Unity party only won about 29.2% of voters, the exit poll suggests.
Their support was hit by public dissatisfaction over the fight against corruption and money-laundering – both key campaign issues.
Latvia shares a border with Russia and about a quarter of its 2.2 million population is Russian-speaking.
The Baltic state is a member of both Nato and the EU putting it on the front line of the increasingly tense relationship between the West and Moscow.
Nato has more than 1,000 troops in the country.
Harmony has said it wants Latvia to stay in the EU and Nato but to have closer economic ties with Russia.
Final results of the election are expected on Sunday and coalition talks could take several weeks.