Israeli newspapers have sharply criticised his performance at a live TV news conference which Mr Sharon called to defend himself and his family against allegations of corruption.
The conference - in which the prime minister made an outspoken attack on the rival Labour Party - was taken off air by the election committee, which judged his remarks to be overtly political.
'Political end'
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Sharon is placing his personality and history on the guillotine
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Ma'ariv
"Yesterday I felt shame for the prime minister," writes a commentator in the centrist Yedi'ot Aharonot. He describes the news conference as "unnecessarily hysterical and aggressive".
"Whoever sent the prime minister yesterday to the press conference, without any readiness to deal with the questions, sent him to his political end," the paper adds.
Writing in the independent Ma'ariv, commentator Shalon Yerushalmi echoes this view. He believes that the conference has damaged Mr Sharon's already scandal-hit re-election campaign yet further.
"The prime minister came out for a world war against all those who seemingly want to eliminate him," it says. And adds: "Today Sharon is almost pleading for the voters' ballots and placing his personality and his history on the guillotine."
"If he goes down in opinion polls next week, this means that the public - not only the left and media as Sharon contends - want to bring the blade down.
Fight for life
Avraham Tirush, also writing in Ma'ariv, agrees.
"This is no longer a defensive battle, it is a battle for life," he says.
He expresses surprise that the election campaign is focusing on only one issue:
"Is Israel's prime minister corrupt or not?" - rather than peace and security, the separation fence, a future Palestinian state, unemployment and the deteriorating economic situation.
"There has never been such a thing before in Israel," Mr Tirush writes.
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Sharon proves he loses all sense of direction when the going gets tough
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Ha'aretz
Past repeated
However, Yossi Verter, writing in the leftist Ha'aretz does see a link between this campaign and a previous one.
He draws parallels between the remarks made by Mr Sharon in the broadcast and a 1999 campaign speech by former Prime Minister Benjamin Netanyahu in which he said Israeli media, "scared" he might win re-election, had enlisted in a drive to ensure his defeat.
"Sharon yesterday proved he too had a bit of Netanyahu in him; he also loses all sense of direction when the going gets tough."
Mr Verter goes on to say that Mr Sharon's speech may have been a deliberate ploy to stop the "vote drain" from his Likud party.
"The propaganda directed at defecting Likud voters resounded in every home of potential Likud supporters in the country; and the answers were only heard by the reporters at the press conference," he says.
Media allegations
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If Mr Sharon cannot answer the allegations he must hang up his hat and go home
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Ha'aretz
Another Ha'aretz commentator calls for Mr Sharon to be forced to answer the corruption allegations, which were originally made in Ha'aretz and Yedi'ot Aharonot.
"In a normal country, the first thing expected of a prime minister suspected of bribe-taking, fraud, breach of trust, who is being question by the police, is to step aside," writes Yoel Marcus.
"Someone who is suspected of such crimes can't simply wash his hands of the whole affair and blame it on the media," he says.
Mr Sharon's claim that he had "no idea" what his sons were up to does not wash well with the commentator, who describes the whole affair as "fishy".
If Mr Sharon doesn't come up with an explanation to satisfy the police and the public he has no choice but "to hang up his hat and go home," he concludes.
BBC Monitoring, based in Caversham in southern England, selects and translates information from radio, television, press, news agencies and the Internet from 150 countries in more than 70 languages.
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