Il Nuovo Postiglione - Pro-EU mayor narrowly ahead in Polish election: exit poll

Trzaskowski was expected to get 30.8 percent of the vote and historian Nawrocki 29.1 percent, according to an Ipsos poll, with neither candidate passing the 50 percent threshold required to win in the first round.

Preliminary results are expected early Monday.

An overall victory for Trzaskowski would be a major boost for the centrist government led by former European Union leader Donald Tusk, which has been at loggerheads with the current nationalist president.

A Nawrocki win would likely extend the political deadlock and analysts predict that fresh parliamentary elections may have to be called.

"This result shows how strong we have to be, how determined we have to be, how much work lies ahead of us," Trzaskowski told supporters in the historic town of Sandomierz in eastern Poland.

The two candidates have widely diverging views on abortion and LGBTQ rights. The election also comes at a fraught moment for Europe as Russia's invasion of Ukraine drags on, far-right populists make electoral gains and ties with Washington are under strain.

"These are very important elections," voter Marcin Woloszynski, a 42-year-old economist, told AFP.

"They offer two diametrically opposed visions of Poland... a democratic, European, open, confident, honest Poland on one side, and the opposite on the other," he said after casting his ballot in Warsaw, a Trzaskowski stronghold.

Anti-communist icon Lech Walesa, who in 1990 became Poland's first democratically elected president since World War II, said the election was a "chance to restore order in our country".

"This is a time of big discussions over the future of Poland, Europe and the world," he was quoted by Poland's PAP news agency as saying.

- Foreign policy, social issues -

The electoral campaign in the EU and NATO member largely revolved around foreign policy, showcasing a clash of philosophies over Poland's engagement with the EU and the United States.

But social issues have also played a major part.

Trzaskowski, 53, has promised to support abortion and LGBTQ rights.

"These elections are about rights for women and minorities, rights for children and animals," said Anna Rusztynska-Wolska, a 69-year-old doctor, after voting.

"They are about security in the European Union and in the world because the more Poland is a country that respects the rule of law (and is) rich and well-managed, the better it will be for all of us," she said.

The former ruling Law and Justice party (PiS), which backs Nawrocki, was frequently at odds with Poland's Western allies and EU institutions in Brussels over rule-of-law concerns.

Nawrocki, 42, is an admirer of US President Donald Trump. He said Trump told him "You will win" when they met at the White House earlier this month.

The key to the election could be whether supporters of Slawomir Mentzen, a far-right candidate who came third in the exit poll with 15.4 percent, back Nawrocki in the second round.

Mentzen is a eurosceptic libertarian staunchly opposed to abortion and migrants.

He has accused the country's one million Ukrainians of taking advantage of Poland.

Anna Urbanska, a 74-year-old pensioner, said the key electoral issue was immigration, which has risen sharply in recent years.

"I don't want these immigrants to be allowed in here, in Poland. I want us to be able to live more peacefully," she said on the eve of the vote.

- High stakes for Europe -

The governing coalition is hopeful a Trzaskowski victory would enable it to carry out undelivered campaign pledges.

Tusk's administration has been prevented from easing Poland's stringent abortion laws and introducing other changes by the president's power of veto.

Poland's head of state is commander-in-chief of the armed forces, steers foreign policy and can introduce and veto legislation.

The stakes are high for Europe.

Under Tusk, a former EU leader, Poland has grown more important on the continent, reinforcing its position as a key voice on NATO's eastern flank against Russia.

E.Spicuzza--INP