Obama scored victories in Georgia, Missouri, Alabama, Alaska, llinois, Delaware, Idaho, Utah, Colorado, Connecticut, Minnesota, North Dakota and Kansas.
However, Obama fell behind in the number of delegates who would support his candidature in the Democratic National Convention. In all, he has 653 delegates as compared to 668 with Hillary.
Media reports attributed Obama's victory in Georgia to the overwhelming support from black voters.
Political analysts have maintained that the Obama momentum should go beyond the South where African-Americans are expected to vote for him in overwhelming numbers.
In Georgia, Obama came away with 77 per cent of the 'younger' voters under the age of 30.
The Democratic fight after 'Super Tuesday' will go all the way to the Convention Floor in Denver this August with both Clinton and Obama fighting for the support of 'Super Delegates' -- about 750 or so prominent Democrats, who have a say in the nomination process.
Clinton will fight on the floor of the Convention to have the delegates of Michigan and Florida counted as well.
The Democratic National Committee had stripped the two states of delegates because they had advanced the primary dates without approval.
Photograph: Paul J Richards/AFP/Getty Images
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