One of the reasons that "Hope" is such a strong message this cycle, is that there is a great desire to put the fear associated with the last 7 years (since 9/11) behind us.
However, fear will beat hope every time, if there seems to be enough danger out there. Tragic news events or terrorist attacks will put hope on hold for a while. But the desire to hope will be even stronger, it just can't emerge unless there is a general sense of safety.
The 3am call ad plays on fear and the danger in the world. The only way to deflect it, is to project a strong sense of an ability to maintain safety. Safety coupled with hope is a winning message.
Generalize "safety" to "security" and include economic security as well as national security and win.
If Obama wants to appeal more strongly to Clinton's core constituencies he has to change his message to include security. He then can back it up with arguments about common sense and 12 years of experience as an elected leader/politician. "Enough experience and common sense to get the important jobs done, not so much as have forgotten what the important jobs are..."