Because there are few substantive differences between the Democratic presidential candidates on the issues, primary voters are left with less-than-ideal metrics like "likeability" and "who Oprah favors."
I'd like to propose a new and better issue with which to make a distinction: Big Money. That is, Hillary Clinton plays the game of money in politics -- and plays it well -- while Obama opts out, arguing that a political system awash in cash can't possibly serve everyday American citizens. The impetus for this argument comes from an article from today's Hill that reveals "Hillary Rodham Clinton (D-N.Y.) has secured more earmarks in the fiscal 2008 defense authorization bill than any other Democrat except for panel Chairman Sen. Carl Levin (D-Mich.)." The article goes on to explain the bill has $5.4 billion in earmarks, 26 of which were requested by Clinton, to the tune of $148.4 million in federal spending. (To be fair, most of the earmarks requested by Clinton were also requested by the senior senator from New York, Chuck Schumer.) According to Taxpayers for Common Sense, Clinton secured 360 earmarks in the four years between 2002 and 2006, worth a combined $2.2 billion.
Contrast all that with Barack Obama, who has only one earmark request in the defense bill. It's a request made by several senators on behalf of a Department of Education program for children with severe disabilities.
This shouldn't be mind-blowing stuff. Consider that after Clinton's bid for comprehensive health care reform failed in the nineties, she went on to become the Senate's second-largest recipient of healthcare industry contributions. Or that her advisers "represent some of the weightiest interests in corporate America." Or that she happily takes campaign contributions from lobbyists and special interests, while Obama has pledged to take no money from such folks, even going so far as to return $50,000 in contributions after he discovered the givers were lobbyists.
Clinton is a divisive figure who voted for the Iraq War, occasionally takes ideologically troubling positions, and whose presidency would perpetuate the dynastic nature of America's presidential politics. I'm not saying I can't support her, but I do find it trying. And her willingness to eat from the money trough while other Democrats try to clean up Washington makes it even more difficult.