Among voters without college degrees, who account for 63 percent of the total, Clinton was the preferred choice of 55 percent. But Obama prevailed among those who had received higher education.

Clinton, considered more trustworthy in handling economic affairs, won the support of 52 percent of voters who are worried about their financial situation, a segment that made up 78 percent of the total Democratic voters.

Democratic presidential candidate Senator Hillary Clinton speaks to supporters at her Ohio primary election night rally in Columbus, Ohio March 4, 2008.(Xinhua/Reuters Photo)