"What we've tried to do is steadily make sure that in each state we are making the case about the need for change in this country. Obviously the people in Mississippi responded," Obama told CNN after his win.

Mississippi had 33 pledged delegates up for grabs, which will be allocated proportionally.

The state's Democratic voters were sharply divided among racial lines, exit polls indicate. As has been the case in many primary states, Obama won overwhelming support from African-American voters. They went for him over Clinton 91-9 percent. See the results

The state has a larger proportion of African-Americans (36 percent, according to the 2000 census) than any other state in the country. And black voters make up nearly 70 percent of registered Democrats.

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