Hillary Clinton won New York early today, according to exit
polls, as Barack Obama polled strongly in
the north east of the United States.
Among the states too close to call early today were New Jersey and Connecticut, all of which were seen
as must-win contests for Mrs Clinton less than a month ago.
Mr Obama won easily in his home state of Illinois and in Georgia, while Mrs Clinton won a
clear victory in Oklahoma and in her home state of Arkansas.
On the Republican side, John McCain was projected to win Illinois, New Jersey and Connecticut and Mitt Romney had a clear lead in his home state of Massachusetts.
In a surprise result former Arkansas governor Mike Huckabee won the first Republican contest to declare, defeating Mitt Romney in West Virginia's presidential convention after most of Mr McCain's supporters swung behind Mr Huckabee in a second round of voting. Mr Huckabee also took his home state of Arkansas.
As Mr Romney cried foul, Mr Huckabee declared himself perhaps the only man in the United States who believed he could win the Republican nomination.
"I still believe in miracles and today I was singing the song Almost Heaven, West Virginia," he said.
In Georgia, the first state to declare that was contested by both parties, Mr Obama emerged early as the clear winner on the Democratic side, with Republicans divided between Mr McCain, Mr Romney and Mr Huckabee.
Mr Obama won 86 per cent of Georgia's black vote but he also won 43 per cent of white voters, almost twice the proportion of white votes he received in South Carolina and Florida.
Mrs Clinton's campaign sought to downplay expectations as the first returns came in and dismissed the Georgia result as a foregone conclusion. "Unlike the Obama campaign, the Clinton campaign never dedicated significant resources to Georgia," the campaign said in a statement.
In Illinois, Mr Obama claimed the majority of votes cast by white women, according to preliminary exit poll results, suggesting that he was eroding a crucial pillar of Mrs Clinton's support.
In another encouraging sign for Mr Obama, Democratic voters across the country said by a margin of two to one that it was more important to choose an agent of change than a candidate with experience.
Only 9 per cent said that electability should be the most important attribute.
Most Republican contests yesterday were "winner takes all" so the candidate with the most votes will claim all of a state's delegates.
Democrats, however, use a form of proportional representation that divides delegates among the candidates, making it more difficult for a clear winner to emerge from Super Tuesday.
Both Mr Obama and Mrs Clinton said in recent days that they did not expect Super Tuesday to decide the Democratic race and both were preparing for a long campaign.
Mr McCain hoped to resolve the Republican race in his favour yesterday but Mr Romney was banking on a strong showing in California to keep the race open.
The candidates were campaigning right up until the polls closed early today, making personal appearances in key states and giving interviews on national and local radio and television.