Sanders wins in New Hampshire

Bernie Sanders won New Hampshire's high-stakes Democratic primary on Tuesday, according to US network projections, leaving rivals including party stalwart Joe Biden in his wake as he staked his claim to challenge President Donald Trump in November.

Sanders, the flag-bearer for the party's progressive wing, had 26 percent of votes with most of the count complete in the northeastern state, where he routed Hillary Clinton in 2016.

"Let me take this opportunity to thank the people of New Hampshire for a great victory tonight," Sanders told cheering supporters.

"This victory here is the beginning of the end for Donald Trump," the senator from neighboring Vermont added as raised the roof with his rallying cry for fairer taxes and health care reform.

Indiana ex-mayor Pete Buttigieg finished in second place at 24 percent as he readied for the more difficult battlegrounds ahead.

Midwestern moderate Amy Klobuchar maintained a late surge to place third on about 20 percent, while liberal Elizabeth Warren finished in fourth at about nine percent. Biden languished in fifth with just over eight percent.

Buoyed by his strong start, Sanders has emerged as the national Democratic frontrunner with 25 percent support, according to a new Quinnipiac University poll that described his surge as a "dramatic shift." Biden has skidded from 26 to 17 percent support since the end of January.