On the last day of campaigning in the US presidential nomination race before Super Tuesday, polls show Senators Hillary Clinton and Barack Obama neck and neck in what is expected to be an extremely close race for the Democratic nomination.
On the Republican side, Senator John McCain now enjoys a wide margin of support in national polls over his nearest rival, Mitt Romney.
The lead Senator Hillary Clinton had maintained over Barack Obama in national polls has been eroded dramatically following the Illinois senator's decisive victory in the South Carolina primary.
Several polls out on the eve of Super Tuesday now show Mr Obama and Mrs Clinton in a statistical tie. A USA Today/Gallup poll shows Senator Clinton just one point ahead of Senator Obama, who has closed a gap of 11 points in the past two weeks.
Senator John McCain has emerged in the same poll as the clear frontrunner in the Republican race with a commanding 42 points over Mitt Romney, who is at 24 points.
All candidates spent the weekend flying across the US to hold rallies.
22 states from the east coast to the west coast will vote tomorrow for their preferred presidential nominee.
