Mohammed Morsi is set to become the first freely elected president in Egypt's history and the first elected Islamist president in the Arab world, according to the country's election commission, a result that marks a pivotal moment in the so-called Arab Spring of pro-democracy uprisings.
Mr. Morsi, the head of the Muslim Brotherhood's political party, won 51.7% in last weekend's runoff presidential election, said Justice Farouq Sultan, the chairman of the election commission, narrowly defeating former air-force general and ousted regime loyalist Ahmed Shafiq.
The victory by an Islamist politician aligned with the Muslim Brotherhood, which was illegal for decades under successive Egyptian autocratic regimes, will send shock waves through an Arab world that for decades has been dominated by Western-backed, secular-minded autocrats.
The election results begin a new diplomatic phase for Western governments that for decades buttressed former President Hosni Mubarak's rule as a bulwark against the powerful Islamists he and other autocrats so often suppressed.
A Morsi presidency threatens to upset a U.S.-backed diplomatic balance. Mr. Mubarak's military-backed, secular rule guaranteed a fragile peace underwritten by the oil-rich Gulf countries and Israel, which relied on Mr. Mubarak to safeguard a 30-year old peace treaty, ensured a measure of stability in the volatile region and protected the Jewish state's western border.
The sight of Mr. Morsi preparing to assume the highest office in the Arab world's most populous nation will likely galvanize the violent uprisings in Syria and Bahrain and buoy the continuing political transitions in Yemen, Libya and Tunisia.
Morsi's win "will be seen as an endorsement of the Arab Spring," said Maha Azzam, an expert on political Islam at the London-based think-tank Chatham House. "It reinforces the possibility of Egypt moving toward becomnig a civil state," she said.
The result's announcement bookends a chaotic and often 16-month transition to civilian rule that began with the ouster of Mr. Mubarak amid massive street protests in February 2011.
But the mood in Egypt's capital Sunday recalled the day of Mr. Mubarak's own departure more than a year earlier. Public squares throughout the country were still filled with throngs of Egyptians pressing for fundamental political changes that have so far proven elusive. News of Mr. Morsi's win set off an outburst of joy from Cairo's Tahrir Square, the focal point of the uprising that felled Mr. Mubarak, as crowds launched celebratory fireworks and waved Egyptian flags.
Toward the end of his long-winded speech that lasted almost 45 minutes before he introduced the results, Mr. Sultan nodded to a fresh start, declaring Mr. Morsi "the president of Egypt's second republic."
Yet Mr. Morsi will assume a presidency crippled by a raft of military-imposed constitutional changes that have only reinforced the sluggish pace of change.
The Supreme Council of the Armed Forces, which has ruled Egypt since February last year has promised to hand over power to the incoming presidency by the end of the month. Much of the military's writ, however, will remain largely in place. The military assumed legislative authority two weeks ago after a high constitutional court ruled to dissolve an Islamist-dominated parliament that until today had been the most tangible credit to Egypt's faltering democratic transition.
Shortly after polls closed last Sunday, the military enraged Islamists and many secular-minded Egyptians by issuing a constitutional declaration that cut short the powers of the presidency.
In the past two weeks, the military has also awarded itself expanded law-enforcement capabilities that some analysts said amounted to a return to military rule.
Thousands of demonstrators, most of whom are aligned with Mr. Morsi's Muslim Brotherhood, have spent the past week in Tahrir Square protesting what some politicians called a military coup.
Delays in the announcement of results kept Egyptians on tenterhooks throughout the past week. Hotels in downtown Cairo on Sunday had boarded their doors and windows in preparation for a violent reaction.