But the resulting judicial charges and political battles that saw Benazir Bhutto's widower spend 11 years in jail will have no bearing on Saturday's presidential election here, and an amnesty last year cleared him of remaining charges.

A secret ballot of the country's two houses of parliament and four provincial assemblies is likely to see Mr Zardari succeed Mr Pervez Musharraf, who was forced to resign last month under threats of impeachment.

Mr Zardari's life journey has taken him from playboy to villain to political heir of the revered Ms Bhutto, whose image still casts a shadow over daily life here nine months after her assassination.

Among the 160 million people of nuclear-armed Pakistan, however, there are doubts over Mr Zardari's suitability for a role that would allow him to dismiss governments and appoint leaders of the country's powerful military.

'Mr Zardari has a controversial reputation. He has been charged, among other things, with corruption, extortion and murder,' Mr Shafqat Mahmood, a former MP and now political analyst, told AFP.

'In the minds of many, he is neither clean nor innocent, and this is a huge drawback in his being a candidate for the highest office in the land.'

Nor has Mr Zardari overcome the view that he was heavily responsible for the ills that befell his wife as prime minister.

The 52-year-old has always maintained the cases against him were politically motivated, and none were proven.

When he married into the Bhutto dynasty in 1987, Mr Zardari, then 31, was the little-known scion of a land-owning polo-playing family from southern Sindh province.

But he quickly carved out a powerful position for himself as a government minister, taking a keen interest in the finance and environmental portfolios.

He was among the first people arrested when his wife's governments were thrown out of office, in what remains an uncomfortable reminder of his notoriety.

The first time, in 1990, he spent three years in jail before rejoining Ms Bhutto's second administration. But he was back behind bars within half an hour of that government's dismissal in 1996.

Mr Zardari then spent eight years in jail - five of them while his family lived in exile - before being freed in November 2004 after being cleared over the last of 17 cases of corruption, murder and drug smuggling.

Ms Bhutto's death last December propelled Mr Zardari back into the political limelight.

After years of being frozen out by the Pakistan People's Party (PPP) led by his wife, he took control and now leads it in a fragile coalition government.

His steadfast stance at the time of Ms Bhutto's killing seems to have placated some internal dissent. The PPP unanimously supported Mr Zardari's candidacy while saying its approval had partly been given in tribute to the sacrifices of his wife.

Mr Zardari's colourful past, however, could prove difficult for Pakistan.

The country is mired by Islamic militancy and has seen nearly 1,200 of its citizens die in bombings and suicide attacks in the past year, seen as a backlash against US ally Musharraf's role in the 'war on terror'.

'There will be people around the world asking questions about the man and it will be very embarrassing for Pakistan,' said Mr Rasul Baksh Rais, political scientist at Lahore's University of Management Sciences.

Chief among countless allegations made against Mr Zardari is that he and his wife used the proceeds of corruption to buy a 20-bedroom luxury estate in Surrey, England.

Although they originally denied having anything to do with the property, Mr Zardari admitted in 2004 that they were in fact the owners.

And in what remains an infamous case, Mr Zardari was accused of conspiracy to kill Mr Murtaza Bhutto, his brother-in-law, who died during a police shootout in Karachi in 1996. The event led to the end of his wife's second term in power.

A court cleared Mr Zardari of the charge in April this year.

Mr Zardari is being challenged in Saturday's election by retired chief justice Saeed-uz-Zaman Siddiqui, backed by former prime minister Nawaz Sharif, and Mr Mushahid Hussain, a close aide of Musharraf. -- AFP