Can Nikki Haley upset Trump in New Hampshire primary?

The tiny state of New Hampshire is voting today in a primary race which could decide if Donald Trump’s path to the Republican presidential nomination is a done deal – or whether his last rival standing, Nikki Haley, can stop him in his tracks.

Mr Trump’s lead in the polls is in double digits, but could New Hampshire, which loves an underdog and has the state motto ‘Live Free or Die’,  land any big surprises?