Acting Israeli Prime Minister Ehud Olmert says he will seek backing from the US and international community for his plans to create permanent borders.
Speaking two days before the elections, he said Israelis must first agree among themselves where the border should lie.
Mr Olmert's campaign has centred on his plan to establish permanent borders.
He has in the past suggested making the controversial West Bank barrier - some of which is being built in occupied Palestinian territory - the border.
But it is hard to see Israel winning broad international support for borders that follow the current route of the barrier, the BBC's Caroline Hawley in Jerusalem says.
Israel says the barrier is crucial for obstructing suicide bombers from the West Bank.
Palestinians say the barrier's main aim is to grab West Bank territory.
A number of UN reports have described the severe humanitarian impact of the barrier on Palestinians.
In 2004 the International Court of Justice issued an advisory ruling that the barrier breached international law where it is built on occupied territory and should be dismantled.
"We should decide on our borders in order to separate ourselves from the Palestinians," Mr Olmert said in an interview on Israeli radio.
"We should have agreement among ourselves on the borders and then negotiate with the international community."
He went on: "I have reason to believe that there is great openness both in the United States and in other countries to listen to our arguments and to debate them in seriousness."
Earlier this month, Mr Olmert said he would unilaterally set permanent borders for Israel within four years if his Kadima party won the election on Tuesday.
The Palestinian leader Mahmoud Abbas warned that such a move by Israel would not bring peace - and the final borders must be decided through negotiation.