Finland's center-left Social Democrats narrowly top poll

Social Democratic leader Party Antti Rinne speaks to the media at the Finnish Broadcasting Company Yle studios in Helsinki, Finland Monday morning, April 15, 2019. Results from Finland's parliamentary election illustrated the struggle by Europe's traditional political parties to retain supporters, with the center-left Social Democratic Party winning the most votes and followed closely by a populist party that wants to temper national efforts to curb climate change. (Antti Aimo-Koivisto/Lehtikuva via AP)

Chairman of The Finns Party Jussi Halla-aho, left, Party Secretary Riikka Slunga-Poutsalo and Campaign manager Ossi Sandvik, right, attend The Finns Party parliamentary election party in Helsinki, Finland on Sunday, April 14, 2019. (Vesa Moilanen/Lehtikuva via AP)

Finland's center-left Social Democratic Party is facing the tough task of trying to form a government coalition after becoming the Nordic country's largest party by an extremely narrow margin following Sunday's highly fragmented parliamentary election.

With all votes counted Monday, the party led by Antti Rinne took 17.7% of votes and 40 seats in the Eduskunta legislature, far from the 101 seats needed for a majority.

Right behind came the populist Finns Party with 17.5%, while the conservative National Coalition party took the third spot with 17% of votes. Outgoing Prime Minister Juha Sipila's Center Party was fourth with 13.8 %.

Tackling climate change and reforming Finland's social and health care system were key topics in the vote where established parties lost support to populists in line with an overall European trend.