The reason is simple: drug companies are prohibited from pro-actively sharing information about their products for uses beyond what the FDA has approved.

FORBES: Governor Rick Perry Puts "Off-label" Medical Therapy on Stage

But some of this political thinking is inertia, because for decades, on issues like the roll-out of generic drugs, the regulatory climate, and strong protections for intellectual property, drug companies were clearly better off with the pro-business Republican party.

FORBES: A Note to The Pharmaceutical Industry Upon The Re-Election Of Barack Obama

The ad is jointly sponsored by Families USA, a pro-reform group, and by PhRMA, the trade association of the prescription drug industry.

NPR: Millions Spent On Ad War Over Health Care Overhaul