Mitt Romney's rivals for the Republican ticket have ripped into the presidential candidate on live TV in a desperate bid to cut his massive poll lead.

Frontrunner Mitt Romney and rivals for the Republican presidential nomination will face off in a high-stakes debate ahead of New Hampshire's primary.

United States Democratic presidential frontrunner Hillary Clinton vowed on Friday there would be no change to her campaign, despite a man taking several people hostage at one of her offices. "I don't see any changes in my campaign or my schedule," Clinton told reporters in Portsmouth, New Hampshire.