Former Vice President Joe Biden has scored crucial early victories in at least eight southern states on Tuesday.
"We were told when you get to Super Tuesday, it may be over," Biden told supporters. "Well, it may be over for the other guy."
It sets him up for a strong position to fight Vermont Senator Bernie Sanders, who picked up California, for the Democratic presidential nomination.
"We're going to win the Democratic nomination and we are going to defeat the most dangerous president in the history of this country," Sanders said.
As Americans voted in 14 states, Edison Research projected Biden the winner in Alabama, Arkansas, Massachusetts, Minnesota, North Carolina, Oklahoma, Tennessee and Virginia.
Meanwhile, Michael Bloomberg, the billionaire former New York mayor, is largely out of the running with only winning in the US territory of American Samoa.
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