The Social Democratic Party declared victory after preliminary results showed it beating the populist Finns Party by a narrow 0.2%. The campaign centered on the welfare system, climate change and immigration.
Finland's center-left Social Democratic Party was on pace to narrowly win parliamentary elections on Sunday, according to preliminary results after more than 99% of votes were counted.
The outcome gives Social Democratic leader Antti Rinne (pictured), a former finance minister, the task of finding coalition partners to form the first left-leaning government in two decades.
What are the results?
Climate and welfare policy
Social Democrat leader Rinne said: "For the first time since 1999 we are the largest party in Finland ... SDP is the prime minister party."
"Let us, my friends, take the Finnish society toward sustainable climate, social and economic policies," he told supporters.
Prime Minister Juha Sipila offered congratulations to the opposition after his Center Party suffered heavily at the polls.
"The Center Party is the biggest loser in these elections. This result is a big disappointment for us. I want to congratulate the winners," he said.
Finns Party chairman Jussi Halla-aho, who received the most votes of any candidate, said he was surprised his party did so well. "I certainly could never have expected a result like this," Halla-aho said. "Honestly speaking, none of us expected this kind of result."
Likely numbers of seats
200 seats were up for grabs in the Eduskunta parliament.
The EU is watching
Finland is set to take over the rotating EU presidency on July 1. European capitals were watching the performance of the Finns Party, which saw its support surge in the run-up to the vote. Many observers expect similar euroskeptic and nationalist parties make strong gains in next month's EU parliamentary elections. The Finns Party is part of a nationalist bloc of European parties aiming to challenge EU policies on migration, security, family and environment.
What were the dominant campaign issues?
Welfare: Sipila's outgoing center-right coalition had sought to implement a health care and social care reform plan, but failed to get it through the legislature. It also implemented unpopular welfare cuts in an attempt to reinvigorate the economy. Rinne advocated for increasing taxes and spending to preserve health and social benefits and a world-class education system.
Read more: Finland keeps crown as world's happiest country
Immigration: Only 6.6% of the population is foreign-born, the lowest rate in Western Europe. Until recently, immigration was only a minor election issue. However, the Finns Party has attracted voters from small towns and villages worried about the issue, especially following highly publicized incidents of alleged sexual assaults by migrants last year. Other party leaders have cautioned against anti-immigrant rhetoric and generalizations about migrants. Rinne supports moderate work-related immigration and taking in some asylum-seekers.
Read more: Climate protection - where do the EU's right-wing populists stand?
Climate change: Most parties support efforts to combat climate change, but they differed during the campaign on how far to go and at what cost. The Finns Party used the debate as a wedge issue to attract voters skeptical of the costs of further action.
What's next?
The outcome means the Social Democrats will have to cobble together a coalition of three or four parties. The fragmented parliament and divisions between parties over welfare reform indicate that coalition talks could be drawn out. During the campaign, most parties voiced reservations about partnering with the Finns Party.
cw,rc/se (dpa, AP, AFP)