Benjamin Netanyahu could be poised for a return to power after exit polls showed the former Israeli prime minister and his allies might win a narrow majority in parliament.
The country's longest-serving premier was helped by a strong showing by the far right.
Mr Netanyahu's right-wing bloc was poised to take 61-62 seats in the 120-seat Knesset, according to television exit polls released shortly after voting closed in the country's election.
The alliance needs to capture at least 61 to form a new government. 70% of the votes have so far been counted.
Mr Netanyahu said: "We have won a huge vote of confidence from the people of Israel.
"We are on the brink of a very big victory."
The polls are preliminary and - with such a wafer-thin majority expected - results could change as votes are counted in the coming hours.
And a final result is not expected until later in the week.
Mr Netanyahu, 73, is currently on trial over corruption charges, which he denies.
He would be able to battle the charges as prime minister, improving his chances of avoiding a conviction or jail time.
Mr Netanyahu said the polls were promising, describing them as a "good start" but they are not the final result.
Sky's Middle East correspondent Alistair Bunkall said a Netanyahu victory "would mark an extraordinary political comeback" for him.
His main rival in the election is the man who helped oust him from power last year, the centrist caretaker prime minister Yair Lapid.
Mr Lapid, who leads a coalition, has warned against the nationalist and religious alliance that would emerge should Mr Netanyahu form a government again.
Read more: Election seen as referendum on Netanyahu
The campaign was shaken up by far-right politician Itamar Ben-Gvir - with his ultra-nationalist Religious Zionism poised to be the third-largest party in parliament after surging from the political margins.
By performing well, Religious Zionism potentially has a strong hand in coalition discussions, Bunkall said.
"It could mean a senior ministerial position for Mr Ben-Gvir, who has previously been convicted for racism," the correspondent added.
Mr Netanyahu has been counting on support from Mr Ben-Gvir and fellow far-right leader Bezalel Smotrich, who have moderated some extreme positions but still say that anyone seen as disloyal to Israel should be expelled from the country.
Far-right politician may seek cabinet post
Mr Ben-Gvir, who has been convicted of incitement for his anti-Arab rhetoric, is expected to seek a cabinet position as head of the ministry that oversees police.
Last month, he brandished a handgun in a Palestinian neighbourhood of Jerusalem and called on police to shoot Palestinian stone-throwers. He has also called for the deportation of Arab politicians.
The election was Israel's fifth in less than four years, with the country gripped by political gridlock.
Mr Netanyahu's opponents view him as a grave threat to Israel's democratic institutions and the rule of law.
He has rejected calls to step down by his rivals, who say that someone who is on trial for alleged fraud, breach of trust and accepting bribes cannot govern. Mr Netanyahu denies wrongdoing.
Voter turnout in the election was reported to be at the highest levels since 1999.