Excluding the war in Iraq, the Democratic presidential contenders at today's Iowa debate steered clear of the campaign's many hot-button issues, discussing instead a range of unexpected social and personal issues and frequently returning to the theme of experience.Much of the debate was couched in language pitting experienced political veterans against new ideas from candidates who haven't spent decades as Washington insiders. Illinois Sen. Barack Obama and New York Sen. Hillary Clinton took center stage, deflecting barbs from the other candidates and leaving former North Carolina Sen. John Edwards, who entered the debate virtually tied for first place with Obama and Clinton in Iowa, according to a recent ABC News/Washington Post poll, struggling to assert himself as a first-tier candidate nationally.