The BBC News website's Martin Asser examines the key questions surrounding the Israeli general election.
Likud and Labour's dominance of Israeli politics is expected to end
Why is there an election now?
Israel holds elections for the 120-seat Knesset or parliament every four years and the next poll had been due in November 2006.
However, last November Prime Minister Ariel Sharon asked to dissolve parliament after splitting from his ruling Likud party.
Mr Sharon had lost support in the right-wing Likud, and from coalition allies, over his unilateral withdrawal of settlers and the troops who protected them from the Gaza Strip and a small part of the West Bank during the summer of 2005.
He considered the move essential for Israel's short-term security.
Mr Sharon also argued that Israel had to give up control of areas containing large Palestinian populations if, in the long term, it was to remain a state for the Jewish people.
But Israel's religious and nationalist constituencies considered the move a betrayal of God's covenant to the Jews and of Israel's past military victories.
They also wanted to avoid probable further withdrawals from Jewish settlements in the West Bank.
However, Mr Sharon - mindful that a majority of secular Israelis supported his plan - decided to pull the plug on Likud, form a new centrist party, Kadima, and go for new elections.
What condition is Ariel Sharon in?
In the middle of this political earthquake, Ariel Sharon suffered first a minor blood clot on 18 December and then - after keeping up his punishing schedule - a massive stroke on 4 January. He has been in a coma ever since.
Although doctors initially said there was every chance Mr Sharon would recover, he has not regained consciousness and the leadership of the new Kadima party has been taken over by his deputy Ehud Olmert.
Since coming to power five years ago, Mr Sharon has become a very popular figure with Israeli voters. Therefore the main selling point for Kadima was that Mr Sharon was at the helm.
His political demise will doubtless have lost the party some voters - however, there is also a consensus for the main plank of Kadima's policy: separation from the Palestinians and drawing Israel's borders with or without a permanent peace deal.
What is at stake in the election?
The main question is how will Kadima perform without Mr Sharon's guiding hand.
If it realises its good position in the polls and Mr Olmert is put in the driving seat, he will follow Mr Sharon's vision of dismantling more isolated settlements in the West Bank and annexing larger settlement blocs where most settlers live.
The settlements are illegal under international law, but Israel argues the law does not apply in the West Bank, and US President George W Bush has at least partly endorsed Israel's view, suggesting it could keep heavily populated areas of the occupied territory.
Likud and other right-wing parties are opposed to any further unilateral withdrawals, which they see as encouraging Palestinian militancy.
Meanwhile the centre-left Labour is fighting under a new leader, the first to come from Israel's traditionally downtrodden North African Jewish sector, Amir Peretz, who has pushed poverty up the election agenda.
If Kadima does succeed, this election could spell the end of the traditional Likud-Labour dominance of Israeli politics, as well as the power of small sect-based parties who have often held the balance of power.
What does it mean for Palestinians?
Palestinians have just emerged from the own election, which resulted in a sweeping win for the Islamic resistance movement Hamas.
Therefore their attention is far more focused on their own situation - with pressure building on Hamas to recognise Israel, renounce violence and sign up to past peace agreements - than the outcome of Israeli elections.
Palestinians usually say it does not make much difference who is in power in Israel - they have to live under the occupation of the Israeli army which does not change very much from government to government.
However, if the unilateralist trend does emerge triumphant from Israel's polls, things could change for the Palestinians in the not too distant future.
Mr Olmert says he wants to draw Israel's final borders by 2010. Palestinians fear that this will leave them living in a series of unconnected Bantustans in the West Bank, separated from a besieged Gaza Strip.
What about the international community?
International efforts are focused currently upon getting Hamas to change its policies, meaning any diplomatic heat is off Israel, whoever becomes the next prime minister.
Although Kadima's plan is endorsed by the US, Mr Olmert is careful to couch his unilateral ambitions within the framework of international diplomacy, ie that his plan will not need to take effect if the international peace plan known as the roadmap succeeds.
However that is a distant prospect, given the growing atmosphere of unilateralism on both sides at the moment.