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Fourteen states and one territory held nominating contests for the Democratic Party's candidate for president on Tuesday, the most pivotal day on the presidential primary calendar.

When the polls closed on Super Tuesday and results came in, it became clear that former Vice President Joe Biden had swept the Southern states, winning the primaries in Virginia, North Carolina, Alabama, Tennessee, Oklahoma, Arkansas and Texas, as well as Minnesota and Massachusetts, and had ended the night with the most delegates. Sen. Bernie Sanders came out on top in Colorado, Utah and his home state of Vermont, NBC News projected.

On Wednesday, NBC News declared Biden the apparent winner in Maine, though the race against Sanders in the state was a tight one.

More than 1,300 delegates — about a third of the total — were at play, more than on any other day in the primary season.

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