Once it is given it is imposible to take away. The longer they wait to kill it the more entrenched it becomes. Either the GOP is waiting for an opportunity secretly to lower the boom on this disaster or thier in on it. My guess is come election time thier will be a more radical conservative party to deal with than the one presently intrusted to get the job moving if not done. Once again 72 billion spent on a day the GOP house cuts 6 billion while patting themselves on the back is evidence.
The answer is in the second part of your response. There are simply too many bribes and payoffs to special interests in the law. State legislatures are discovering new means of power and tax revenue as they implement the state level insurance exchanges. Besides, the GOP controlled house has made their token effort to block the law, so they can say they tried. It is the money, always follow the money.