Obama and Clinton neck and neck: poll

Though Mrs Clinton has regained some momentum since her surprise win in last week's New Hampshire primary, her comeback has failed to halt Mr Obama's rise in the polls on the back of his sweeping victory in the Iowa caucus on January 3.

The one-time presumptive nominee held a 21-point edge over Mr Obama in October, a lead which he had cut to 8 points by December. The latest Reuters/Zogby poll, however, indicates she now leads Mr Obama by just 39 to 38 percent. With the 1-point gap well within the poll's margin of error of 4.7 points, the results mean she can no longer lay claim to frontrunner status.

“This the definition of a hard-fought race,” John Zogby, the pollster, said.