Democratic presidential candidate Bernie Sanders has surged in the latest CNN national poll, climbing 10 points since July.
The independent Senator from Vermont is now a close second to Hillary Clinton. Sanders is currently on 29 per cent, while Clinton holds a shaky and falling lead at 47 per cent, down 9 per cent since July.
The CNN/ORC poll shows Sanders picking up momentum, with Clinton close to losing her stable and secure lead.
It also shows Biden with 14 per cent support, though he is yet to announce whether he will enter the race.