Who wrote the Affordable Care Act?

[Puzzledtraveller]

The PPACA is a massive piece of legislation. It was not written overnight. It had to have been conceived and drafted in some part even before the president was sworn in, if not elected. I know the official legislation would have been written by congress but there had to be a pretty big framework already in place for a law of this magnitude. I know people reference Romneycare and other models from the past that have been proposed but I cannot help but get the feeling that the ACA was already on a backburner just ready for the right time and right president to make it possible.