The commission published data from 99.9% of voting districts by provinces at 6.27am without giving an overall result.

The data shows Trzaskowski and Nawrocki well ahead of other candidates in 15 of 16 provinces.

A late exit poll by Ipsos from Sunday’s first round showed Trzaskowski leading with 31.2% of the vote, ahead of Nawrocki on 29.7%.

If confirmed, the result would mean that Trzaskowski and Nawrocki will go head to head in a run-off vote to determine whether Poland sticks to the pro-European track set by prime minister Donald Tusk or moves closer to a more nationalist agenda.

Both candidates started preparing for the second round early today, with Trzaskowski meeting voters in Warsaw and Nawrocki in Gdansk.

“We need to talk to everyone, arguments are the most important. I am glad that many young people went to vote, but the big challenge is to convince them to vote for me,” Trzaskowski told reporters.

Far-right candidates Slawomir Mentzen and Grzegorz Braun together accounted for more than 21% of the vote, a historically high percentage, winning widespread support from young voters. It is not clear, however, who their votes will go to in the second round.

Nawrocki, backed by the nationalist Law and Justice (PiS) party, said he will fight for the votes the people on both sides of the political landscape.

“My social agenda and the fact that I will be the guardian of the social achievements of the Law and Justice government and the Solidarity (trade union) make it an offer also for left-wing, socially sensitive circles,” he said.