Most Americans support the US House provision setting a timetable that calls for US troops' withdrawal from Iraq by September 2008, said a survey released.
According to the CBS News poll released on Wednesday 59 per cent of those surveyed favoured the provision while 37 per cent opposed it.
The poll was conducted before Tuesday's Senate vote to include a non-binding withdrawal timetable in its version of legislation providing continued funding for military operations in Iraq and Afghanistan.
US President George W Bush has pledged to veto either version of the legislation and has reiterated his opposition to the timetable.
The survey also found that while most Americans believe Iran is providing weapons to insurgents in Iraq, the majority sees that Iran as a threat does not require military action by US.
The poll was conducted among a random sample of 831 adults nationwide, interviewed by telephone on March 26-27.