[cnn-photo-caption image= http://i.cdn.turner.com/cnn/2008/images/04/23/art.analysis.gi.jpg caption=" Did Clinton's win come too late?"](CNN) - Hillary Clinton scored a big victory in Pennsylvania on Tuesday to keep her hopes for the Democratic nomination alive. The question is whether the win came soon enough.
Barack Obama's loss in another big state and the margins by which he lost among blue-collar and rural voters on Tuesday, on the other hand, may raise questions about his electability.
Some polls had shown Clinton with a double-digit lead in Pennsylvania. But in the weeks between the last primaries in Ohio and Texas, Obama had whittled down Clinton's advantage.