ISLAMABAD (AFP) - Millions of Pakistanis are expected to brave Taleban threats on Saturday to vote in elections that mark a historic democratic transition in the nuclear-armed state ruled for half its life by the army.
The Taleban have branded democracy un-Islamic and have waged a virulent campaign of attacks against the main secular parties, killing more than 120 people in what has been called the country's deadliest election.
Polls open at 8:00 am (11am Singapore time) and close at 5:00 pm, allowing an electorate of more than 86 million to vote for the 342-member national assembly and four provincial assemblies in Khyber Pakhtunkhwa, Punjab, Sindh and Baluchistan.
The vote marks the first time that an elected civilian administration has completed a full term and handed power to another through the ballot box in a country where there have been three military coups and four military rulers.
The front-runner is ex-prime minister Nawaz Sharif, head of the centre-right Pakistan Muslim League-N (PML-N), but much of the campaign has been electrified by cricket star Imran Khan with promises of reform and an end to corruption.
The charismatic 60-year-old leader of Pakistan Tehreek-e-Insaf (PTI) tapped into a last-minute surge of support after fracturing his spine when he fell from a stage at a campaign rally on Tuesday.
Although he is expected to make a full recovery, he is flat on his back in hospital and aides say he cannot even vote on Saturday.
The outgoing centre-left Pakistan People's Party (PPP) has run a lacklustre and rudderless campaign, with its chairman, Bilawal Bhutto Zardari, too young to run and largely hidden from public view due to Taleban threats.
Its campaign has instead starred its two dead leaders, founder Zulfikar Ali Bhutto, who was hanged under military rule in 1979, and his charismatic daughter Benazir Bhutto, assassinated in a gun and suicide attack in 2007.
"This election is very important because for the first time we have crossed five years of real democracy," Mr Mohammed Jahangir, 30, told AFP.
"I think this is going to be the start of true democracy in Pakistan. We are moving in the right direction - either PTI comes or N-league comes. Both parties are good," added Mr Jahangir, a journalist for a business newspaper.
Turnout will be crucial. Commentators are divided on whether a wealth of enthusiastic first-term voters and Taleban threats will make turnout higher or lower than the 44 per cent at the last elections in 2008.
With around 30 per cent of voters aged under 30, young people are expected to play a decisive role and provide key support for Mr Khan's PTI, which boycotted polls in 2008 and won one seat in 2002.
The main issues are the tanking economy, an appalling energy crisis which causes power cuts of up to 20 hours a day, the alliance in the US-led war on Islamist militants, chronic corruption and the dire need for development.
The umbrella Tehreek-e-Taleban (TTP) stepped up their threats on the eve of the elections, warning voters to boycott polling stations to save their lives.
"To revolt against this system, the TTP have planned several actions on May 11, so we appeal to the people to stay away from polling stations to save their lives," Taleban spokesman Ehsanullah Ehsan said.
More than 600,000 security personnel have deployed nationwide and around half the estimated 70,000 polling stations have been declared at risk of attack, many of them in insurgency-torn parts of Baluchistan and the northwest.
The Human Rights Commission of Pakistan has warned that the violence has already impaired the fairness of the elections "almost beyond repair".
The PML-N and PPP have dominated politics for decades, led by two of the richest families in the country, the Sharifs and the Bhuttos. But Mr Khan has sought to galvanise a young, urban middle class with promises of sweeping change.
Kinship and patronage traditionally determine voting, particularly in the countryside and while Mr Khan led a high-energy campaign, drawing enormous crowds around the country, it remains unclear how many seats he can win.
With no reliable polling data, Mr Sharif has been earmarked the most probable winner but if PTI do well enough to become a formidable opposition, there are concerns that the emergent coalition will be weak and possibly short-lived.
Mr Sharif served as prime minister from 1990-93, when he was sacked for corruption, and from 1997-99, when he was deposed by the military, although his family say he is a changed man who will this time govern more successfully.
Both he and Mr Khan have backed talks with the Taleban and criticised US drone strikes against Islamist militants, although it remains unclear if or how policy towards extremism would change under a new government.