HELSINKI >> Finns will vote Sunday to elect a new president at an unprecedented time: the Nordic nation is now a NATO member following Russia’s invasion of Ukraine, and its eastern border with Russia is closed, both almost unthinkable a few years ago.

Unlike in most European countries, the president of Finland holds executive power in formulating foreign and security policy, particularly when dealing with countries outside the European Union like the United States, Russia and China.

“Clearly, the main task of the president is to steer foreign policy,” said Teivo Teivainen, professor of world politics at the University of Helsinki.

Some 4.5 million citizens are eligible to vote for Finland’s new head of state from an array of nine candidates — six men and three women — and pick a successor to hugely popular President Sauli Niinistö, whose second six-year term expires in March. He is not eligible for re-election.

Recent polls suggest that former Prime Minister Alexander Stubb, 55, and ex-Foreign Minister Pekka Haavisto, 65, are the top contenders in Sunday’s first round of voting. None of the candidates are expected get more than 50% of the vote, pushing the race into a runoff in February.

Stubb, who headed the Finnish government in 2014-2015, and Haavisto, who is running for the post for the third time, are both estimated to gather 23%-27% of the votes, followed by Parliament speaker and far-right politician Jussi Halla-aho with around 18%. Bank of Finland governor Olli Rehn was expected to receive about a 14% share of the votes.

A brief look at a map shows why foreign and security policy matters are important political themes in this northern European country of 5.6 million people: Finland shares a 1,340-kilometer (832-mile) border with Russia.

Candidate debates on television and media coverage have largely focused on Finland’s new role as a member of NATO, as well as the situation in neighboring Russia and its effects on Finland’s security. The war in Ukraine — where Finland is among the top European providers of military and humanitarian aid to Kyiv — and Israel’s war with Hamas in the Middle East have also emerged as key topics in the race.

Teivainen, the professor, said the head of state’s overall influence in Finland has strengthened due to its NATO membership and the growing importance of security issues in recent years, not least because of Russia’s invasion of Ukraine, which has deeply affected Finns.

Abandoning decades of military non-alignment, which guaranteed pragmatic and friendly relations with Moscow ever since the end of World War II, Helsinki opted to join NATO in May 2022 together with Nordic neighbor Sweden. The government’s decision, endorsed by Niinistö and strongly supported by the citizenry, was a direct result of Moscow’s assault on Ukraine, which started on Feb. 24 the same year.

Finland became the Western military alliance’s 31st member in April last year, much to the annoyance of Russia and President Vladimir Putin.

NATO membership and a war raging a mere 1,000 kilometers (600 miles) away from Finland’s border “stresses the security policy dimension” in the duties of the president, who also acts as the supreme commander of the Finnish military, Teivainen said.

“The threat of war is now a much more concrete thing,” he said.

Compared to the previous election in 2018, the geopolitical status of Finland — which for decades maintained a careful balancing act between the East and the West — has made an about-face and presidential candidates have focused in their speeches on the nation’s new role as a NATO front-line country.

Under the Finnish Constitution, the president decides on foreign and security policy issues together with the government. He or she also appoints the prime minister and government members, signs bills into law, and acts as a moral leader of the nation on major issues.

In a practice that has become a rule during the reign of Niinistö, Finland’s president since 2012, the prime minister, currently Petteri Orpo, focuses on EU issues in the foreign policy arena, while the president deals with other countries and largely stays out of domestic politics.

Niinistö has won praise among Finns for maintaining close ties and seeking dialogue with his counterparts in Moscow, Washington and Beijing to help the Nordic nation punch above its weight and bring attention to its positions.

Since the start of Moscow’s Ukraine assault nearly two years ago, the Finnish president’s ties to Putin have ceased to exist. Moscow has harassed Finland with a range of retaliatory measures — apparently due to its NATO membership and Helsinki’s enhanced military cooperation with Washington — from cyber attacks to threats of Russia’s increased military activity in the Baltic Sea region.

“It’s utterly important for us to keep connection not only with the United States but also with China and, as soon as it’s realistic, with Russia,” Niinistö told Finnish public broadcaster YLE earlier this month.

Late last year, Finland closed its border with Russia after some 1,300 migrants without proper documentation or visas arrived across the frontier just months after Finland joined NATO.

With such “hybrid warfare” Helsinki suspects Moscow is trying to undermine the Nordic country’s security by sending undocumented migrants across the frontier — a claim that the Kremlin denies.

Finland acts as the European Union’s external border in the north and makes up a significant part of NATO’s northeastern flank.

All eight Finland-Russia border crossing points for passengers have been closed since Dec. 15. The southeastern rail checkpoint for cargo trains in Vainikkala remains open for now.