ISLAMABAD - Pakistani legislators are set to elect as president the late Benazir Bhutto's controversial widower Asif Ali Zardari on Saturday, making a choice many Pakistanis see leading to a fresh phase of political instability.

His wife's assassination last December and the victory of her grieving party in a February election has catapulted Zardari to the top in Pakistan's switch to civilian-led democracy after nine years under former army chief and president, Pervez Musharraf.

The presidential vote is a three-way contest, but Zardari's party and its allies have a clear majority among lawmakers in the two-chamber parliament and four provincial legislatures that make up the electoral college.

Desperate for stability in a nuclear-armed Muslim state whose cooperation is key to victory over al Qaeda and the success of the West's mission in Afghanistan, the United States is counting on Zardari to keep Pakistan committed to the war on terrorism.

"I will work to defeat the domestic Taliban insurgency and to ensure that Pakistan territory is not used to launch terrorist attacks on our neighbours or on NATO forces in Afghanistan," Zardari said in an article in the Washington Post on Thursday.

The United States doesn't trust his chief rival Nawaz Sharif, fearing he could pander to Islamists.

The dangers that lie ahead were underscored on Wednesday by an unsuccessful assassination attempt on Prime Minister Yousaf Raza Gilani, a Zardari nominee, that the Pakistani Taliban claimed responsibility for.

IMAGE PROBLEMS

Zardari's been called a crook, a liar, and held in widespread disdain, and there have even been doubts raised about his mental fitness after the rigours of 11 years spent in jail.

Loyalists say the allegations were politically motivated and powerful media groups were smearing Zardari's image, while favouring Sharif, the prime minister Musharraf overthrew in 1999.

"No one challenges his democratic credentials as head of an elected party, but the personal credibility of Mr. Zardari has become a serious issue," wrote Shaheen Sehbai, editor of the Jang Group of Newspapers, Pakistan's largest newspaper group, in The News daily last week.

Zardari's hesitancy to bring back judges Musharraf dismissed because of fears they could revive corruption cases against him, has not built confidence.

Zardari, who was investment minister in the second government of his slain wife, was released after an eight-year stretch in 2004, but he has never been convicted.

Charges against him and Bhutto were dropped last year under an amnesty introduced by Musharraf for politicians and civil servants as part of an attempt to cut a deal with Bhutto.

GRAVE TIMES

The coalition government led by his Pakistan People's Party has struggled to rise to the challenges left behind by Musharraf after coming to power five months ago.

Inflation is running at more than 25 percent, the rupee is at all-time lows, foreign currency reserves barely cover three months of imports, the stock market has dropped 41 percent from a life high in April, and an Islamist militancy is surging across the northwest.

Until Musharraf ended months of speculation by resigning last month, Zardari had denied having any interest in an elected post.

Even detractors show grudging admiration for hiss manoeuvres to bring together a coalition that forced Musharraf to quit by threatening to impeach him.

That didn't satisfy Sharif, who pulled his party out of the coalition days later because of Zardari's stalling over the restoration of the judiciary.

Analysts fear a return to the bitter rivalry of the 1990s that made the army lose patience with civilian leaders.

On Tuesday, a government prosecutor said he wanted corruption cases against Sharif taken up in a sign that Pakistan's politics was reverting to type.

Analysts say Zardari should realise Pakistanis are looking for real democracy rather than yet another leader who believes that once elected he can do what he pleases.

"He will have to operate within the institutional parameters of the presidency, very different from the existing mode where he has relied on deals and "understandings" with enormous power but hardly any accountability or official responsibility," Talat Masood, an ex- general turned analyst, wrote in the Daily Times.