We regret to inform you that the proposed Democratic Presidential Debate scheduled for April 27 has been cancelled due to time constraints and logistical issues associated with such a large, national event.
...Barack Obama's advisers refused to accept an invitation to debate in North Carolina because they did not want to give Hillary Clinton any excuse to stay in the race beyond Tuesday, assuming she doesn't fare that well....
Could it be because during the last debate, he showed his lack of ability to answer the "tough" questions? Then his supporters cried foul at the "unfair" questions. He looked bad after the last one. I don't think he will be in too big of a hurry to jump into another one.