(CNN) -- The strongest contender to become the next Pakistani prime minister is hardly a newcomer to the country's political stage. Nawaz Sharif, 63, has had a long and rocky career that includes two stints as prime minister during the 1990s, ordering Pakistan's first nuclear tests, a showdown with the nation's powerful military, time in jail and years of exile. After spending the past several years in opposition to the governing Pakistani People's Party (PPP) -- which has struggled to tackle the country's crippling problems of militant violence, chronic power shortages and a flagging economy -- Sharif now has a shot at another stint in office.
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Nawaz Sharif, a frontrunner in Pakistani elections, has been prime minister twice
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He was overthrown in a 1999 coup and went into exile in Saudi Arabia
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He is now campaigning with a promise to revive Pakistan's economy
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Observers have raised questions about his stance on extremism and terrorism
Nawaz Sharif
Sharif
Nawaz Sharif
Religious conservatives, some of whom sympathize with extremist groups, make up an important part of @placeholder's core vote, Rumi said.