Polish Prime Minister Donald Tusk has claimed victory in parliamentary polls after exit polls gave a clear lead to his Civic Platform party.
Initial results suggest Mr Tusk's centre-right party won almost 10% more than its conservative challenger, the Law and Justice Party.
Opposition leader Jaroslaw Kaczynski has admitted defeat.
Civic Platform is the first Polish party to win two consecutive terms since the fall of communism in 1989.
The official results from Sunday's election are due to be published on Monday.