Super Tuesday 2020: Biden secures initial win in southern states, Sanders takes Vermont

US Democratic presidential candidate and former Vice President Joe Biden secured a big win in the southern US states, including Virginia, North Carolina, Alabama and Tennessee on Super Tuesday.

Front-runner Senator Bernie Sanders, as expected, won his home state of Vermont, CNN reported.

Biden's big early wins enshrine one of the most remarkable comebacks in modern political history.

A week ago, his campaign showed poor innings in the first three nominating contests in Iowa, New Hampshire and Nevada. But a massive win in Saturday's South Carolina primary now appears to have triggered a rebound that appears to be expanding in the 14 states that voted on Tuesday.

Virginia was seen as a significant test of Biden's strength against former New York City Mayor Michael Bloomberg, who is facing voters for the first time in the 14 nationwide primaries after a half-billion-dollar advertising blitz.

Meanwhile, the results in Alabama and North Carolina confirm the former vice president's strength among African American and affluent suburban voters on whom he is basing his campaign.

According to early exit polls, around 3 in 10 Democratic voters in North Carolina decided who to vote for in the last few days. Almost 3 in 5 of those voters supported Biden -- suggesting that the departures of Former Mayor of South Bend Pete Buttigieg and Minnesota Senator Amy Klobuchar helped consolidate voters behind the former vice president.

Sanders and Biden are the early leaders in Minnesota, Maine and Oklahoma and the two are also in the early lead in Massachusetts along with Senator Elizabeth Warren, who is hoping for a win in her home state.

Voting also took place Tuesday in Democratic primaries in Arkansas, Colorado, Massachusetts, Minnesota, Tennessee and Utah.

Early Super Tuesday projections and results suggested a disappointing night could be in store for Bloomberg and Warren, who both need to make a statement to have a rationale for staying in the race.

As votes are counted, both rivals were below the 15 per cent threshold needed to win delegates in several states.