If you want to know why Republicans aren't going to repeal the Affordable Care Act, consider this political ad in Connecticut by Dan Malloy:
The heart of it is an attack on Republican Tom Foley, who favors repeal:
Now, Foley has a health care plan for us: allow insurance companies to discriminate based on preexisting conditions, and deny coverage for breast and prostate cancer screening and autism treatment.
The public has always favored health care reform. The Affordable Care Act lost majority support due to the ungainly legislative process, and the fact that opponents were able to seize upon unpopular details. Most of all, it became associated with Washington at a time when the public is angry at just about everyone in power.
But once Republicans propose repeal, then they're not just standing against something. They're for something. They have a plan. And their plan involves all kinds of horrible things.
When you're the one proposing a plan, then you become part of the system. You're "Washington," you're doing something that people are going to be skeptical of. And it's not exactly hard to find unpopular details in the repeal plan, because it involves restoring a cruel, dysfunctional status quo.