Looking around the internets, there seem to be two ways that the GOP intends to undo what has been done.
(1) Constitutional challenge to the law itself. Several state attorneys general plan to file a lawsuit challenging the newly passed law, on the grounds that the federal government cannot constitutionally require citizens to purchase health insurance.
Without getting too deep in the constitutional thicket, the Constitution (the Commerce Clause, specifically) permits the federal government to regulate interstate commerce. For well over a century, this has been held (by courts) to include the regulation of anything that effects interstate commerce. And that is pretty broad. Too broad, conservatives argue.
But Commerce Clause jurisprudence is pretty abundent and shows that Commerce Clause regulation is indeed pretty broad. Recently, the Supreme Court held that even marijuana sales that take place entirely within the boundaries of one state still effect interstate commerce (of marijuana)… and Congress can therefore pass laws proscribing it. (More recently, the ban on partial birth abotions was seen, somehow, as being a law which effects interstate commerce).
Besides, the Court has upheld the extensive federal role in health care through such programs as Medicare and Medicaid. This new law is a change in degree, not in kind, and courts will likely stay out of the way.
The twist here is that rather than forbidding people to buy something (marijuana), the new health care laws require people to buy something (health insurance). But that, I would argue, is a distinction that fails to go to the Commerce Clause. Failure of everybody to buy health insurance still effects interstate commerce. Therefore, Congress has the power to mandate health insurance.
Some have asked this question: "Okay. Well, could Congress require every American to buy a GM car? The cumulative effect of individual failure to buy a GM car has substantial effects on interstate commerce. Your telling me that would be okay?"
My answer to that is this: "No, in my view, such a law would not be 'okay'. But would it be constitutional? No." And here's why: it doesn't satisfy the "necessary and proper" clause. You see, not only must a law effect interstate commerce, but it must be "necessary and proper" to the legislative objective of that law which effects interstate commerce. There simply is no reason twhich makes it necessary for people to buy GM — and only GM – cars.
The same cannot be said for health care reform. You cannot make reforms to the health insurance industry unless you mandate universal coverage.
It's an interesting argument, but ultimately, one that will fail.
(2) Repeal the law. Republicans expect to win back the House and Senate later this year for midterm elections. And they intend to run on campaign promises to repeal health care reform. (In fact, the crazy Michelle Bachmann just introduced legislation to repeal the bill that just passed).
This strikes me as a political tactic bound to fail. For one thing, healthcare reform will have already started, and people will like it.
The obvious question to such GOP candidates will be this: "What part do you want to repeal first? The part where insurance companies can no longer drop your coverage when you get sick? The part where insurance companies can deny coverage because of a pre-existing condition? Do you want to repeal the Medicare 'donut-hole'?"
These are among the many changes in health care that Americans — even, I suggest, the staunchiest teabaggers — will like. Right now, a lot of Americans are still fearful of "death panels" and "killing grandma". But Republicans can't run on repealing those things — because they don't exist (and never did)! So what exactly will they be repealing?
There's an even greater problem that comes with "repeal the law". Under congressional rules, you need a 2/3rd majority to repeal an existing law. What does that mean? That means that Republicans would need 290 votes in the House. Even assuming that all 36 Democrat dissidents (those who voted against health care reform) stay true, it still means that Republicans would need a seventy-six seat gain in the House in the 2010 elections. Possible, but unlikely.
And worse yet, Republicans would need a twenty-six seat gain in the Senate. It will never happen, because only 26 Democrats are up for re-election this year. The GOP will have to win them all. Chances: almost nil.
Don't be fooled: the "repeal the law" meme is just a cynical attempt to keep the GOP based fired up and contributing money. It has absolutely no chance of actually happening.