With about 60 lawmakers elected to the 329-seat parliament, Abadi was set to be re-elected for a second term, several senior political figures told AFP.

Abadi's Victory Alliance list was followed by the anti-establishment alliance of Shiite cleric Moqtada Sadr and the communists, who for three years have protested each week against corruption and for an overhaul of the political class.

Political sources said that alliance -- Marching Towards Reform -- had won some 51 seats.

Third place was taken by the Conquest Alliance, made up of former fighters of the mostly Shiite Hashed al-Shaabi paramilitary units which played a key role in fighting the Islamic State group.

Led by former commander Hadi al-Ameri, the group has won around 30 seats, the officials said.

Those trailing further behind include Vice President Ayad Allawi, who presented a Sunni-majority list, and former prime minister Nuri al-Maliki who lost the leadership after IS overran the city of Mosul.