"We definitely are going to stick to the timetable of elections in January," he said on Sunday after talks with UK Prime Minister Tony Blair in London.
"Democracy is going to prevail and is going to win in Iraq."
Violence and instability across Iraq have raised doubts the elections, crucial to US plans for a legitimate democratically chosen government, can be held on time.
UN Secretary General Kofi Annan said last week "credible elections" would not be possible if security in Iraq remained as poor as it was now.
Hopes of improvement
US Secretary of State Colin Powell echoed that judgment, but predicted the security situation would improve by then.
If Iraq's electoral timetable were to falter, it would prove awkward for Blair as he prepares to fight his own election next year, hoping by then the Iraq war would have faded in the nation's memory.
Allawi urged the United Nations to step up its support for Iraq as the vote approaches, calling "upon the United Nations to help us in providing whatever it takes to make the elections a
Earlier in the day, Iraq's Foreign Minister Hoshiyar Zibari criticised the UN for a lack of help to organise the poll.
"They are not doing enough to help us. Up until now they have only about 30 international staffers in Baghdad," he told BBC television.