Not so much GOP ideas (except for Romney of course, who has clearly supported it in the past, including at the federal level, until it hurt him to do so); wasn't it from the Heritage Foundation or some similar conservative think tank?
Once again, I am baffled by the GOP position on this. The individual mandate spreads the cost of health care across a larger swath of health care users. It reduces the burden placed on paying customers, insure or direct private pay, by reducing the number of uninsured who get their care for free.
It is a mechanism by which people, who currently don't pay anything, pay for health insurance, thereby evening out the burden and increasing personal responsibility.