The two candidates ended the debate on a friendly note, but the pressure is on Clinton. She has lost 11 straight primaries and caucuses to Obama and lags behind him in the number of delegatesObama dismissed the charge out of hand, then turned the jeers to applause when he countered, "What we shouldn't be doing is tearing each other down, we should be lifting the country up."
The exchange marked an unusually pointed moment in an otherwise civil encounter in the days before March 4 primaries in Texas and Ohio -- contests that even some of Clinton's supporters say she must win to sustain her campaign for the White House.
The former first lady has lost 11 straight primaries and caucuses, and trails her rival in convention delegates. Obama has won a pair of big union endorsements in the past two days.
In a university auditorium in the heart of Texas, the two rivals agreed that high-tech surveillance measures are preferable to construction of a fence to curtail illegal immigration.
They disagreed on the proper response to a change in government in Cuba in the wake of Fidel Castro's resignation. Clinton said she would refuse to sit down with incoming President Raul Castro until he implements political and economic reforms. Obama said he would meet "without preconditions," but added the U.S. agenda for such a session would include human rights in the Communist island nation.
They also sparred frequently about health care, a core issue of the campaign.

