A U.S. District Court in Michigan has refused a request for injunction of Obamacare's individual mandate provision (requiring everyone to buy health insurance or face a federal penalty). The opinion lays out a brief history of Commerce Clause adjudication in the Supreme Court before addressing the merits of the arguments at hand. It's worth a read, particularly because it is short, legible and seemingly intended for a non-legal audience.
The significance of the ruling is only of particular interest because it is the first official ruling on Obamacare. It is only a denial of the plaintiff's request for injunction - the court was merely required to find a reasonable basis for constitutionality (not actual constitutionality) for denial. The ruling will be appealed.
Further, two independant suits have been brought in other courts. A federal judge already refused to dismiss a challenge to Obamacare in Virginia, meaning to case will proceed. And another suit brought by twenty states and small-businesses is pending in Florida. A victory in any of these three courts would demand Supreme Court review of the law.
Should that day come, it will be of particular significance to Obama and the Democrats. The lack of a severability clause in the law, requiring that the whole law be held void if a single provision is found unconstitutional, could swiftly and easily effect the end of Obamacare. The principle acheivement of the Obama administration would not only be nullified, but it would be found unconstitutional and many Tea Party criticisms would be vindicated.
A heavily reduced Democratic presence in Congress would leave the president with a difficult decision: accept defeat or compromise with Republicans. The loss of a near-super-majority in Congress will likely prove crippling to a president so unwilling to compromise.