New Hampshire voters are having their say on the Democratic Party’s chaotic presidential nomination fight. The state’s presidential primary Tuesday will determined which candidates are stronger or weaker after Iowa’s chaotic caucuses last week. Vermont Sen. Bernie Sanders and former South Bend, Indiana, Mayor Pete Buttigieg began the day as the undisputed front-runners. New Hampshire also offers a critical test for former Vice President Joe Biden and Massachusetts Sen. Elizabeth Warren. Warren faces the prospect of an embarrassing defeat on her near-home turf. And Biden is traveling to South Carolina, where he hopes to make a strong showing among black voters later this month.