Poles will choose on Sunday a new president with the twin brother of the late Polish president and the interim head of state facing each other in a tight vote.
A total of 25,774 polling stations, including 263 abroad and five on Polish-flagged ships, have opened on Sunday. The turnout forecast is some 54 per cent.
The first round of early elections, forced by President Lech Kaczynski's death in the April air crash in western Russia, was held June 20. It was narrowly won by acting president Bronislaw Komorowski (41.54 per cent), a pro-EU, moderate member of the governing Civic Platform party.
His main opponent Jaroslaw Kaczynski, an ex-prime minister who now leads the conservative Law and Justice party, was second with 36.46 per cent of the vote.
Numerous surveys, conducted before the elections, were unable to clearly predict the outcome, as the margin between the two candidates has shrunk from some 10 per cent to figures below the error margin limit in the past week.