(CNN) -- Poles headed to the polls Sunday to elect a new head of state to replace President Lech Kaczynski, who was killed in a plane crash in April.
The election pits Kaczynski's twin brother, Jaroslaw Kaczynski, against Parliament Speaker Bronislaw Komorowski, who has been acting president since the crash.
The two are among 10 candidates in the election originally planned for the autumn but brought forward after Kaczynski died.
Jaroslaw Kaczynski, once prime minister, is a divisive figure in Polish politics. His far-right Law and Justice party runs on a nationalist platform with the slogan, "Poland comes first".
"Poland has to be a strong country, otherwise it will not exist," he said recently. "I want to tell everyone here that as president I won't just be the head of state -- I will look after the strength of the Polish nation".
Recent polls show him trailing Komorowski, who is in the lead. The Parliament speaker is a moderate running for the center-right Civic Platform.
