Polish Prime Minister Donald Tusk claimed victory Sunday after exit polls showed his party winning a clear majority of votes, BBC reports. His rival and predecessor, Jaroslaw Kaczynski, has admitted defeat.

The New York Times reports that final election results are not expected until Tuesday.

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Polls suggest that Tusk's center-right party, Civic Platform, won nearly 40 percent of the vote, giving it 10 percent more votes than Kaczynski's Law and Justice Party, BBC states. The win will mean that the Civic Platform party will be the first party in the Eastern European nation since the fall of Communism in 1989 to win two consecutive parliamentary elections.

“It is a success of optimistic Poland,” Tusk told supporters Sunday, as reported in the Times. “I would like to thank all Poles for the fact that four years later, in this most significant act of democracy, which is the universal vote, that they confirmed once again that those moments back then were meaningful, and that these four years were deeply meaningful for Poland, all Poles, and for us.”

Reuters reports that financial markets will welcome the win for Tusk's party because it will signal political and economic stability in Poland.

Tusk won a snap election in 2007 and then presided over four years of growth, BBC states.