1. Obama can't run on a record of accomplishments; so he has to tear Romney down.
2. Team Obama has internal polling that shows they are losing....going negative is always a sign that a candidate believes he is losing.
Look for Obama to get more extreme in his negative attacks; as November looms, the Olympics end, the Republican Convention bump happens, and voters focus on the ultimate question:
Do we want 4 more years of this guy ?
http://www.cbsnews.com/8301-505267_1...-new-extremes/