WARSAW, Poland (AP) — Poland is set to hold a presidential runoff election on Sunday between two candidates offering starkly different visions for the country’s future.

The winner will succeed President Andrzej Duda, a conservative who is finishing his second and final term. The outcome will determine whether Poland embraces a nationalist populist trajectory or pivots more fully toward liberal, pro-European policies. An exit poll by Ipsos will be released when polls close on Sunday at 9 p.m. local time, with a margin of error of plus or minus 2 percentage points. Final results are expected Monday.

Whoever wins can be expected to either help or hinder the agenda of the centrist government of Prime Minister Donald Tusk thanks to the presidential power to veto laws.

The vote comes amid heightened regional tensions driven by Russia’s war in neighboring Ukraine, security concerns across Europe and internal debates about the rule of law.

It follows a first round on May 18, in which Warsaw Mayor Rafał Trzaskowski won more than 31% of the vote and Karol Nawrocki, a conservative historian, earned nearly 30%. Eleven other candidates were eliminated.

Opinion polls show the two men running neck and neck. Other factors add to the unpredictability. Nawrocki did much better in the first round than surveys had predicted, indicating that his strength was underestimated. On the other hand, large numbers of Poles abroad have registered to vote in the second round, which could help Trzaskowski.

Nawrocki is a 42-year-old historian who was tapped as by the national conservative Law and Justice party despite a lack of political experience or party membership. But this is seen as acting in his favor, as the party, which governed for 2015-2023, seeks to refresh its image before a parliamentary election in 2027.

Nawrocki’s supporters describe him as the embodiment of traditional, patriotic Polish values. They believe U.S. President Donald Trump's support for him will strengthen Poland's ties with the United States and make the country safer.

Trzaskowski, 53, is Warsaw’s mayor and a close ally of Tusk. A deputy leader of Civic Platform, a pro-European Union party, he has been prominent in national politics for years. This is his second presidential bid after narrowly losing to Duda in 2020.

Supporters credit him with modernizing Warsaw through infrastructure, public transit expansion and cultural investments. He is widely seen as pragmatic and focused on strengthening ties with other European nations.

Nawrocki recently received a boost from Trump and other U.S. conservatives, who see the Polish election as part of a global battle between liberal and populist right-wing forces.

His campaign has echoed themes popular on the American right, including skepticism toward EU bureaucracy and emphasis on Christian identity. His supporters feel that Trzaskowski, with his pro-EU views, would hand over control of key Polish issues to Paris and Berlin.

Nawrocki also has been endorsed by the Trump administration and conservative Hungarian Prime Minister Viktor Orbán.

Many European centrists are rooting for Trzaskowski, seeing in him someone who would defend democracy as it faces pressure from authoritarian forces across the globe. He has received the support of new centrist Romanian President Nicusor Dan — who recently defeated a far-right nationalist.

Nawrocki has faced a number of scandals over the past months, but it's not clear that they are hurting him. In fact, they might have the opposite effect. Many right-wing voters don't believe the allegations and accuse the media of using its power to hurt him, creating what appears to be a rallying effect around him.

Nawrocki himself has acknowledged that he took part in an organized brawl including football hooligans in 2009. A former boxer, he said he has taken part in various forms of “noble male battle” in his life.

Polish media have also reported on his connections to gangsters and the world of prostitution.

Tusk accused Law and Justice party leader Jarosław Kaczynski of tapping Nawrocki despite questions about his past.

“You knew about everything, Jarosław. About the connections with the gangsters, about ‘fixing girls,’" Tusk wrote on X. "The entire responsibility for this catastrophe falls on you!”

1. Security and war in Ukraine: With Russia’s war in Ukraine in its fourth year, Polish voters are acutely attuned to issues of regional security. Both candidates support continued backing for Ukraine, but to different degrees. Nawrocki believes that Ukraine should never join NATO, while Trzaskowski believes Ukraine should be allowed to join one day when the current war is over.

2. Rule of law and democracy: Trzaskowski has pledged to support the restoration of judicial independence and repair relations with the EU, which viewed changes by Law and Justice as anti-democratic. Tusk has tried to change some legislation, but has faced resistance from the the outgoing president, Duda. Nawrocki, while less outspoken than his party patrons, is seen as likely to preserve Law and Justice’s changes that politicized the courts.

3. Women’s rights: Abortion remains a divisive issue in Poland, especially after a near-total ban was imposed under Law and Justice. Trzaskowski supports loosening restrictions and has backed proposals to legalize abortion up to 12 weeks. Nawrocki opposes any liberalization and has campaigned as a defender of traditional conservative values.