Pakistan is set to elect its third consecutive civilian government in Wednesday's parliamentary elections.
A look at the main candidates and their parties:
Shahbaz Sharif, Pakistan Muslim League
Shahbaz Sharif took over as chief of the beleaguered center-right former ruling Pakistan Muslim League party after the Supreme Court last July ousted his elder brother and then-Prime Minister Nawaz Sharif from office on charges of corruption stemming from the leaked Panama papers. Shahbaz was twice chief minister in Punjab province, where 60 percent of Pakistan's 200 million people live.
Nawaz Sharif, who is now in jail appealing a 10-year prison term for corruption, has had a tumultuous relationship with Pakistan's powerful military despite entering politics at the military's behest. Shahbaz Sharif, by contrast, has maintained balanced ties with the military.
Imran Khan, Tehrik-E-Insaf Party
Former cricket player Imran Khan heads the center-right Pakistan Tehrik-e-Insaf party. He is expected by many to be the next prime minister but faces his stiffest competition from the Pakistan Muslim League. Khan acquired a reputation as a playboy during his cricket career but has embraced conservative Islam as a politician. He has denigrated Pakistan's liberals, expressed support for a Taliban-style justice system and aligned himself with radical religious leaders.
Khan's party, which he founded in 1996, did not made a strong showing until 2013, when it became the third-largest party in parliament. Khan has been a strident critic of Nawaz Sharif, vowing a "new Pakistan" free of corruption. He is widely seen as a preferred choice of the military.
Bilawal Bhutto Zardari, Pakistan People's Party
Bilawal Bhutto Zardari, 29, is the son of the slain former Prime Minister Benazir Bhutto. His Pakistan People's Party's political strength lies in southern Sindh province. Since his mother's assassination by Taliban militants in 2007, the party's fortunes have dwindled. Benazir Bhutto served as prime minister twice and had returned to Pakistan in an attempt to return to power when she was attacked and killed.
The Bhutto family has been dogged by tragedy. The party's founder, Zulfikar Ali Bhutto was ousted in a military coup and hanged by dictator Gen. Ziaul Haq. Both his sons were killed by unknown assailants. Benazir Bhutto's only surviving sibling, her sister Sanam, lives in Britain and has stayed out of politics. Benazir's husband, Asif Ali Zardari, served as Pakistan's president for five years until 2013. He is seeking a seat in parliament in Wednesday's elections.
Bilawal Bhutto has tried to revive the party's dwindled popularity by leading rallies despite election-related violence but analysts do not believe he can win a simple majority.
Muttahida Majlis-E-Amal Alliance
The parties in the Muttahida Majlis-e-Amal alliance, or MMA, represent the four schools of religious thought in Pakistan — the three Sunni schools: the Deobandi, Brelvi and Ahle Hadith — and the Shiites.
Maulana Fazlur Rehman, a pro-Taliban, anti-U.S. radical Islamic leader, heads the alliance of radical religious groups that ruled Pakistan's northwest from 2002 to 2007 following the Sept. 11, 2001, attacks in the United States.
In Wednesday's elections, the hard-line parties are once again trying to gain seats in parliament and the provincial assemblies, focusing their ambitions mainly in the country's northwestern region bordering Afghanistan, where they hope conservative Pashtuns will support their candidates and their anti-U.S. agenda.
In the past, the MMA had made political gains by opposing U.S. involvement in Afghanistan. It was dormant for 10 years until leaders of right-wing religious parties decided to revive it and allow it to participate in Wednesday's elections. The MMA has 191 candidates running for seats in the National Assembly and 404 candidates running for seats in the four provincial legislatures. Reasonable success in the vote may prompt other parties to seek its support in forming a coalition government.
Mohammed Ahmed Ludhianvi, Ahle Sunnat Wal Jammat Party
Headed by a viciously anti-Shiite leader, Mohammed Ahmed Ludhianvi, Pakistan's radical Sunni militant Ahle Sunnat Wal Jammat, or ASWJ, is also taking part in Wednesday's vote. The ASWJ is an offshoot of the banned Sipah-e-Sahaba Pakistan, a radical religious party that reviles Shiite Muslims as heretics and has been accused of violent attacks against them.
ASWJ is not registered with the elections oversight body but its candidates are running for seats as independents both for the provincial legislatures and the National Assembly. According to party spokesman Oneeb Farooqi, it fielded 170 candidates.
The Pakistani government recently asked authorities to unfreeze Ludhianvi's bank accounts and assets and remove the ban on ASWJ, drawing criticism from rights groups and analysts who question the government's seriousness in tackling extremism.
Ludhianvi is also running for a seat in the National Assembly from a district in Punjab province.
Hafiz Saeed, Allah-O-Akbar Tehreek Party
Hafiz Saeed, who has been declared a terrorist by the United Nations and the United States, is leading the campaign for candidates of the radical Allah-o-Akbar Tehreek party after the Pakistan Election Commission refused to register his Mille Muslim League party.
Saeed has a $10 million US-imposed bounty on his head in connection to allegations that he masterminded the 2008 attacks in Mumbai that killed 166 people.
A radical cleric, Khadim Rizvi, heads the Tehreek Labbeik party, which has made enforcement of the blasphemy law a central plank in its campaign. The law calls for an automatic death penalty for anyone deemed to have insulted Islam or the Prophet Muhammad. Frenzied mobs have gone on rampages and killed people at the mere suggestion that at an act of blasphemy has been committed. Critics say the law is used to incite violence and also to settle individual grudges.
Khadim Hussain Rizvi, Tehreek Labbeik Party