The rivals for the Democratic presidential nomination are taking part in a television debate in Texas.
The rivals for the Democratic presidential nomination are taking part in a television debate in Texas.
Next month's primary in the state is seen as crucial for both Hillary Clinton and Barack Obama.
Next month's primary in the state is seen as crucial for both Hillary Clinton and Barack Obama.
Mr Obama is now the favourite for the party's nomination, and he gained even more momentum by winning the Democrats Abroad primary on Thursday.
Mr Obama is now the favourite for the party's nomination, and he gained even more momentum by winning the Democrats Abroad primary on Thursday.
The Texas debate is a major test for the flagging Clinton campaign, coming after 11 consecutive poll defeats.
The Texas debate is a major test for the flagging Clinton campaign, coming after 11 consecutive poll defeats.
Along with Ohio, Texas votes on 4 March, in a contest that is widely being seen as a must-win for the former first lady.
Along with Ohio, Texas votes on 4 March, in a contest that is widely being seen as a must-win for the former first lady.
She has not won a nominating contest in more than two weeks.
Call for change
Mrs Clinton opened Thursday night's debate at the University of Texas in Austin by saying it was up to those voting in forthcoming state primaries to decide the outcome.
Supporters of both contenders rallied ahead of the debate
"If you'll be part of this campaign - which is really your campaign, about your futures, your families, your jobs and your health care - we'll continue to make a difference for America," said Mrs Clinton.
Mr Obama, for his part, reiterated his call for change.
"Washington has become a place where good ideas go to die, because too many politicians are interested in scoring points rather than bridging their differences to get things done," said the Illinois senator.
The Texas debate is the first of two to be held ahead of 4 March primaries in Texas, Ohio, Rhode Island, and Vermont.
In previous televised debates, Mrs Clinton has attempted to outweigh Mr Obama's rhetoric with her grasp of policy issues.
But Mr Obama has brushed off criticism that he lacks substance.
Union backing
Mrs Clinton now needs a majority of the remaining delegates to beat Mr Obama.
Mrs Clinton now needs a majority of the remaining delegates to beat Mr Obama.
He has at least 1,353 - according to an Associated Press projection - of the 2,025 delegates he needs to secure the Democratic nomination at the party's convention in August.
He has at least 1,353 - according to an Associated Press projection - of the 2,025 delegates he needs to secure the Democratic nomination at the party's convention in August.
Mrs Clinton has 1,264 delegates.
Mrs Clinton has 1,264 delegates.
In previous televised debates, Mrs Clinton has attempted to outweigh Mr Obama's sparkling rhetoric with her firm grasp of policy issues.
Correspondents say the blue-collar vote will be crucial in the Ohio and Texas contests, and the Clinton campaign has already begun targeting lower-income workers in its ads.
But in his drive to become the first black US president, Mr Obama has recently gained support from some powerful unions, including the Teamsters and the Service Employees International Union.
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