Moving on from Ariel Sharon is going to be difficult for a party that registered itself the day before its founder’s stroke and whose bright new posters bear the website address www.kadimasharon.org. But even without its 77-year-old figurehead, life must go on for a party whose Hebrew name means “Forward”.

Yesterday, as doctors reported signs of movement on the comatose Prime Minister’s left side, his political heirs were clustered inside the party’s three-storey headquarters near the city of Petah Tikva, putting together a nationwide network of branches and grassroots activists.

As they did so, Mr Sharon’s anointed successor, Ehud Olmert, was making his first big decision as acting Prime Minister: allowing Palestinian parties to campaign in east Jerusalem, an overwhelmingly Arab area that Israel has held under occupation since 1967.

Israel had objected to Hamas participating in the poll on January 25 because it was committed to destroying Israel. But Mahmoud Abbas, the Palestinian President, threatened to call off the election if voting were banned in east Jerusalem.

Mr Olmert, a former Mayor of Jerusalem, has drawn praise for his sensitive handling of the medical crisis. But whereas Mr Sharon bestrode the political and military arenas, Mr Olmert must assemble a team, relying on Shimon Peres, the former Prime Minister, for experience and Shaul Mofaz, the Defence Minister and a former general, to make up for his lack of military credentials. Although support for Kadima has held up in opinion polls, this could prove fragile.

“They don’t say it publicly, but the strategy will be to raise Olmert’s profile as the one who preceded Sharon on the road to disengagement, and that he was Kadima before Sharon,” Yuval Karni, a political writer with Yediot Ahronoth newspaper, said.

“If Olmert continues not to make mistakes and keep a low profile, he will gain more legitimacy. But you can’t tell how long it will last. Just after Rabin’s assassination Shimon Peres was very strong in the polls, but he lost popularity within three months.”

However, the party mechanics are already falling into place. Party managers have set up a professional call centre that they say has recruited 25,000 members.

Avigdor Yitzhaki, a former Likud administrator who is the Kadima campaign manager, said that the party would soon appoint chairmen of 130 local branches, mostly mayors who defected from other parties. Because 14 Likud MPs also defected to Kadima, it will receive a £1.3 million slice of the money Likud received from the Government.

Gideon Doron, a political scientist at Tel Aviv University, said that Kadima could gain 40 of the 120 seats in the parliament. “Sharon was the glue that stuck it all together,” he said. “The question is now if Olmert will be able to provide the glue. I think he will. Once you have been Mayor of Jerusalem, that’s more than enough to give you credibility.”

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