The populist Shi'ite cleric, a longtime adversary of the United States, was a surprise win for Iraq. The preliminary results were based on a count of more than 91 percent of the votes cast in 16 of Iraq's 18 provinces.
Sectarian discord in Iraq is mounting, and new prime minister Haider al-Abadi must convince Sunnis, Shiites and Kurds to keep working together in a united Iraq. He's Iraq's best hope, but even a change in leadership may not be enough.
Political tensions have calmed in Baghdad, but unrest in Iraq has given power — and weaponry — to the Shiite militias who stepped up to help fight ISIS. Now no one is sure if they'll still listen to the Iraqi government or look after their own interests.
Iraq has a new problem on its hands: A political showdown between current Prime Minister Nouri al-Maliki and his would-be successor. And the wrangling and potential violence are taking place against a backdrop of a massive humanitarian crisis and American intervention in northern Iraq.