Here's the question:
"Can you guarantee that all the small donor contributions to the campaign will be used for electing Clinton president instead of paying back the $5 million loan and ending up in her pocket?"
I think it's a fair question. Suppose that Sarah Saintly, a widow living on a small fixed income, gives her last extra cash to the campaign in the belief that Clinton had the best chance to beat the Republicans and enact a progressive legislative agenda. Sarah has the right to know whether a portion of her money will not be used for that purpose and instead be redirected into the pocket of the multi-millionaire Clinton family. And if the Clintons loan more money to their campaign as has been suggested, an even larger-percentage of Sarah's donation goes the the Clintons instead of the purpose Sarah intended.
Some other questions: what are the terms of the loan? Does the campaign have to pay back with interest? That could really lend itself to abuse. The McCain campaign released the document showing the bank loan it received - can we see the actual document?
When will we know if Clinton will loan more money to her campaign, and how much? Will Bill Clinton loan money to the campaign? Is there any legal distinction between a loan from Hillary and a loan from Bill?
It might be a little difficult for the Obama campaign to push the issue - prominent supporter John Kerry apparently did the exact same thing as Clinton in 2004. Still they should - it's the right thing to do and will help their campaign. And nothing would stop reporters from asking these questions.