Voting is underway in the American state of New Hampshire, with former President Donald Trump and his former ambassador to the UN, Nikki Haley, facing off to be the Republican nominee. 

It comes after Trump's victory at the Iowa caucus and rival candidate Ron DeSantis dropping out and endorsing the ex-President. 

US Correspondent Richard Arnold told Tim Dower that it's Nikki Haley's last stand. 

He says latest polls give Trump a 22-point lead over Haley, and says it looks like Trump will seal the deal. 

LISTEN ABOVE 

• "Uphill battle" for Haley as DeSantis endorses Trump
• New Hampshire likely to lock in Trump's candidacy -Strategist