Tel Aviv  - The only certainty to emerge from exit polls and the first official results in Tuesday's Israeli election is that nothing is certain.

Three separate exit polls on Israel's three television news channels gave the centrist Kadima party of Foreign Minister Tzipi Livni a sparse, two-seat lead over the hardline Likud of former premier Benjamin Netanyahu, and first initial results, which began trickling in after midnight, showed the margin closing to just one seat.

The gap was small enough to allow both Livni and Netanyahu to claim victory.

More important, though, is who will be entrusted with the task of forming a new government, once President Shimon Peres completes his consultations with leaders of the parties that make it into the Knesset.

By law, the president can ask anyone to form a government, but in practice, the nod has been given to the candidate with the best chance of forming a coalition, which is traditionally but not automatically the leader of the largest party.

On Tuesday night, the exit poll results showed that since the right-wing block, which the Likud heads, had a clear majority of mandates in the 120-seat Knesset, Netanyahu has the best chance of forming a coalition.

Banking on the support of the right-wing parties in the Knesset, Netanyahu already proclaimed Tuesday night that he will be the next prime minister, but Livni was reportedly counting on a public outcry if Kadima wins the most seats but she is denied the first chance to form a coalition.

Even if Livni is chosen over Netanyahu, she might find it difficult to form a coalition. Netanyahu may well refuse to negotiate with her, knowing that without Likud she would struggle to stitch together a stable government.

And if she is unable to form a coalition in the allotted time, Peres can then call on Netanyahu to try to set up a government.

Such a scenario is not without precedent in Israel.

In 1984, though the Labour Party won a narrow, three-seat victory over the Likud, it was unable to form a government. The Likud, which was then asked to try, was equally unsuccessful. The final result, after weeks of governmental paralysis, was a national unity government where Labour leader Shimon Peres and Likud leader Yitzhak Shamir rotated the premiership, each serving for two years.

Nobody was talking about rotation on Tuesday night, but with the final results not yet in, they were perhaps hoping they would not have to. And final results in Israel have a habit of making victory parties seem premature.

The most famous instance occurred in the 1996 prime ministerial elections, when Israelis went to bed with exit polls showing Labour Party leader Peres holding a narrow lead over Likud's Netanyahu, only to awake the next morning to find that according to the actual results, Netanyahu was on his way to the prime minister's office.

That, however, was a direct election for prime minister. Tuesday's poll in Israel was a parliamentary election, with the premiership going to the candidate best able to form a coalition.

The key here is the hardline, nationalist Yisrael Beteinu party, projected to become the third-largest faction in Parliament. Party leader Avigdor Leiberman said in his post-election speech to supporters that he preferred sitting in a "nationalist, right-wing government," pointing him clearly toward Netanyahu.

Whether Netanyahu would prefer to head a narrow coalition, comprising smaller parties who could threaten coalition stability if their demands are not met, is another issue.

"One thing is clear," analyst Ben Caspit wrote in Ma'ariv on Tuesday. "Either the winner today forms a genuine national unity government tomorrow ... or things are going to be very bad." (dpa)