Sanders leads Buttigieg, Klobuchar at halfway point in New Hampshire: US media

Frontrunner Bernie Sanders was leading at the halfway point in New Hampshire's Democratic primary on Tuesday, with Pete Buttigieg and a surging Amy Klobuchar battling for second, US media reported.

With just under 50 percent of polling stations reporting, Vermont's leftist senator Sanders was at 28 percent, with young Indiana ex-mayor Buttigieg at 23 percent and Minnesota senator Klobuchar at 20 percent.

Joe Biden, part of the Democratic hierarchy and for months the national frontrunner, was limping home in fifth with just nine percent, raising doubts over the viability of his candidacy.