Michele Bachmann ends presidential campaign

Minnesota congresswoman Michele Bachmann has ended her presidential campaign, after finishing at the back of the field in Iowa's caucuses.

Her exit leaves six Republicans in the race to challenge Barack Obama for the White House in November.

Mitt Romney, who narrowly won in Iowa, meanwhile rolled out an endorsement from ex-Republican nominee John McCain.

Rick Perry, who came fifth in Iowa, vowed to press on to the next battleground state of New Hampshire.

Steve Kinsgtone reports.