Debate focuses on health care , Obama , economy . John Edwards , Obama keep it cordial , draw comparisons to ex-Sen. Clinton . Clinton pushes experience , Obama pushes judgment . Obama won the season-opening Iowa caucuses , then finished second to Clinton in every contest until last week 's South Carolina primary -- which he won with a commanding 55 percent of the vote in a three-way race . Candidate John Edwards did n't meet criteria , was n't invited .
Debate focuses on health care , Obama , economy . John Edwards , Obama keep it cordial , draw comparisons to ex-Sen. Clinton . Clinton pushes experience , Obama pushes judgment . Candidate John Edwards did n't meet criteria , was n't invited .