Israeli Prime Minister Benjamin Netanyahu and challenger Benny Gantz have both claimed victory in Tuesday's election.
Exit polls have predicted a parliamentary majority for rightist parties under the incumbent but a big showing for Gantz's party.
"We won! The Israeli public has had its say!" said Gantz's centrist Blue and White party, which two out of three exit polls saw taking more seats than Netanyahu's conservative Likud.
A third exit poll predicted the two parties would be tied.
However, two of the polls predicted that right-wing parties would together take more than 60 of parliament's 120 seats, forming a bloc that Netanyahu could marshal to form the next coalition government.
The third exit poll predicted this bloc would be tied with centre-left parties tilted toward Gantz.
"The rightist bloc led by Likud has won a clear victory," Netanyahu said in a statement. "I will begin forming a right-wing government with our natural partner this very night."
Netanyahu, 69, has leaned heavily on his friendship with fellow right-wing politician Donald Trump on the campaign trail.
Should he secure a record fifth term and he would become Israel's longest-serving prime minister in the summer.
