Polish presidential candidate Bronislaw Komorowski was leading in the second round of elections according to exit poll results after voting stations closed Sunday, dpa reported.
Komorowski, of the centre-right Civic Platform party, had won 53.1 per cent of the vote in the runoff, exit polls said.
His opponent Jaroslaw Kaczynski, of the right-wing Law and Justice party, had received 46.9 per cent of the vote.
Poles went to the polls Sunday in a presidential runoff vote held early to find a successor to Lech Kaczynski, who died in a plane crash in April. Official results are expected early Monday.
"Our Polish democracy has won," Komorowski said Sunday. "And even though we'll have to wait for the big bottle of champagne tomorrow, I think we have enough reason for pride and joy."
The campaign had been "especially difficult because it took place in the shadow of the tragedy," he said.
Voter turnout was at 42.1 per cent by 5 pm (1500 GMT) Sunday, said the state electoral commission at a press conference.
Sunday's election follows a first round of voting on June 20, in which no candidate secured a majority.
Long lines formed at polling stations on the Baltic coast, northern Poland, where thousands cast their vote during their vacations. There were also crowds in Hurghada, Egypt, another popular tourist destination for Poles, reported TVN 24.
Both candidates had cast their votes by the afternoon: Kaczynski in his native Warsaw, and Komorowski in Mackowa Ruda, a rural retreat in northeastern Poland where he was spending the weekend.