With the Democratic presidential race heading toward a possible climax Tuesday as four states including Texas and Ohio conduct their primaries, the lagging Hillary Clinton campaign has cut back its efforts to win over those superdelegates who have pledged to2008 Election 2008 Elections Activism Media Barack Obama Barack Obama Barack Obama And Ohio Primary Barack Obama And Texas Primary Breaking Off The Bus News Citizen Journalism Politics Citizen Journalism Superdelegates Clinton Campaign Hillary 2008 Hillary Clinton Hillary Clinton Hillary Clinton And Ohio Primary Hillary Clinton And Texas Primary John McCain Marc Cooper March 4 Primaries March 4 Primary March 4 Voting Obama 2008 Offthebus Rhode Island Primary Superdelegate Investigations Superdelegate Transparency Project Superdelegates Superdelegates Democratic Convention Superdelegates Democratic Nomination Superdelegates Democratic Party Superdelegates Democratic Primary Superdelegates Howard Dean Superdelegates Media Attention Vermont Primary Who Are The Superdelegates Barack Obama Barack Obama 2008 Barack Obama 60 Minutes Barack Obama Muslim Smear Barack Obama Muslim Smear 60 Minutes Hillary 2008 Hillary Clinton 2008 HIllary Clinton 60 Minutes Hillary Clinton Barack Obama Hillary Clinton Obama As Muslim Obama 2008