The results from Baghdad - where Mr Allawi was expected to do well - show the one-time CIA protege with only 140,364 votes compared to 350,069 for the alliance, which is headed by the Shia cleric who lived in Iran for many years.
Among the mostly five Shia provinces tallied so far, the alliance's lead is even wider. It has 1.1 million of the 1.6 million votes counted at 10 per cent of polling centres in the capital and the Shia south. Mr Allawi's list was second with 360,500. "Large numbers of Shia voted along sectarian lines," said Sharif Ali bin Hussein, head of the Constitutional Monarchy Party. "Americans are in for a shock. A lot of people in the country are going to wake up in shock."
Safwat Rashid, a member of Iraq's Independent Election Commission, and international poll officials warned observers not to read too much into the numbers, which did not include Sunni or Kurdish provinces.
Mr Rashid said the vote total would not be known for another 10 days, although numbers from polling the Iraqi diaspora abroad had been ratified.
About 170,000 Iraqis living overseas cast ballots, with 44 per cent voting for the Sistani list, 18 per cent for the Kurdish list, 12 per cent for Mr Allawi's list and 8 per cent for the main Christian Iraqi list.
Meanwhile an ambush on a road near Baghdad yesterday killed two policemen, wounded 14 and left at least 16 missing on the worst day of violence since last Sunday's election.