US Democratic Senator Barack Obama of Illinois beat Senator Hillary Rodham Clinton of New York in the Mississippi presidential primary on Tuesday as expected, US media forecasts and exit polls showed.

Obama, an African-American, had been expected to win in the state, given the demographic factors favorable to him.

African-Americans account for 36 percent of Mississippi's population, higher than any other state, and blacks constitute more than half of the Democratic electorate.

Obama has swept states with large African-American electorates so far and he has been leading by between six and 24 percentage points in polls since last week.

In Tuesday's race, he was expected to collect a majority of the 33 delegates at stake, but Clinton would also garner a share because the delegate allocation is proportional, not winner taking all.

Mississippi holds open primaries, which means independents and Republicans can vote in the Democratic contest.

Exit polls indicated that Obama was winning the votes of independents and Republicans who cross over and cast ballots in Democratic contests.

For Mississippi, it was a moment to bask in the national spotlight.

And for a state with images of a strictly segregated past, the Democratic primary was a chance to alter some long held stereotypes.

"We're seeing a contest where I think you're going to see a huge turnout of voters voting either for a woman or an African-American, and that gives us a chance to make a statement," said Marty Wiseman, a professor of political science at Mississippi State University.

While the polls closed in Mississippi, results were reported from last week's contest in Texas.

According to CNN estimates, Obama won the Texas Democratic caucuses and would get more delegates out of the state than Clinton, who won the state's primary.

Under the Texas Democratic Party's complex delegate selection plan, Texas voters participated in both a primary and caucuses last week.

Two-thirds of the state's 193 delegates were chosen at the primary, while the remaining third were decided by the caucuses.

(Xinhua News Agency March 12, 2008)