WATCH: Democratic candidates debate ahead of New Hampshire primary

MANCHESTER, N.H. (AP) - Four days before the New Hampshire primary, the major Democratic contenders were hunkered down preparing for Friday night's debate and largely off the campaign trail during a critical stretch in which undecided voters are anxiously trying to make up their minds.

WATCH the debate below from ABC News:

New Hampshire's Feb. 11 primary could be more important than ever this year, following Iowa's muddled results.

The AP was unable to declare a winner because of the tight margin between Sanders and Pete Buttigieg and irregularities in the caucus process.

The campaigns are expected to shift into overdrive on Saturday, starting with a major state party dinner.