New Hampshire votes in 1st primary

New Hampshire began voting on Tuesday in the first US presidential primary with Republican Donald Trump calling on supporters to propel him to victory and Democrat Bernie Sanders primed to upstage Hillary Clinton.

The northeastern state, home to just 1.3 million people, sets the tone for the primaries and could shake out a crowded Republican field of candidates pitting Mr Trump and arch-conservative Senator Ted Cruz against more establishment candidates led by Senator Marco Rubio.

Kicking off the primary in a time-honoured tradition, the handful of voters in Dixville Notch, one of three small communities to vote at the turn of midnight, went to the polls.

Mr Sanders took four votes to none for Ms Clinton, while Republican Ohio governor John Kasich received three to Mr Trump’s two.

But everything still remains in play in New Hampshire due to a high number of registered independents, who can choose to vote in either party, along with up to 30 per cent of voters who were still undecided in the days before polling.

“This is crunch time,” the Republican frontrunner Mr Trump told thousands of cheering supporters at an event delayed slightly by snow in Manchester late Monday.

“You have to go out, you have to vote, we have to celebrate tomorrow evening,” added Mr Trump. “Let’s have a big, big victory.”

On the Democratic front, Ms Clinton will be looking to confound polls that predict her insurgent challenger, Senator Sanders of neighbouring Vermont, will gallop to victory in the state.

The RealClearPolitics poll average shows the self-described democratic socialist — who has called for nothing short of a “political revolution” — leading 53.3 per cent to 40.5 per cent for Ms Clinton in New Hampshire.

Ms Clinton won Iowa by a hair, but Mr Sanders is keen to show that his campaign, built on economic fairness for all, can give the former secretary of state a run for her money deep into election season.