Pakistan set to elect new head of state
Likely winner Hussain will shore up the PM's authority and provide stark contrast to Zardari
Boycotted by the opposition Pakistan People's Party, which complained it was not consulted on bringing the election forward from August 6, Sharif's candidate is certain to win.
Mamnoon Hussain is a businessman, close ally of the premier and a long serving member of the main ruling Pakistan Muslim League-N (PML-N), and comes from the southern province of Sindh.
His loyalty to Sharif and low-profile will shore up the prime minister's authority and provide stark contrast to Zardari, considered a sharp political operator behind the scenes.
Supporters say Hussain's election could be important domestically by giving the south some stake in the federal administration, otherwise dominated by Punjab, Sharif's power base.
There is a crisis of leadership ... [Zadari's son] needs his father behind him
The PPP withdrew its candidate Raza Rabbani after the Supreme Court accepted a PML-N request to change the date as lawmakers would be busy with pilgrimage and prayer at the end of Ramadan.