Health care expert Tevi Troy, writing in the new issue of Commentary, predicts that 2015 will be the worst year for Obamacare yet–not just because the steady (and delayed) implementation of the law will arouse new opposition, but because the Congress that takes office this week was partly elected on the basis of broad public opposition to the law. That opposition, he notes, could begin to cross party lines, with the possibility of votes on small changes to Obamacare that could override a presidential veto.

Troy notes:

The first aspect of the law the GOP will probably address is the “medical-device tax.” This 2.3 percent tax on medical devices is supposed to bring in $30 billion in revenue, but it is better understood as a tax on innovation. One of the reasons it is the bill’s most politically vulnerable aspect is that some Democrats, including Minnesota Senators Al Franken and Amy Klobuchar, join the Republicans in opposing it. (Minnesota happens to be the capital of the medical-device industry.)

Even if such changes do not go through, Obama cannot protect the law forever: “President Obama can engage in a holding action to protect the ACA from legislative changes over the next two years. But he cannot hold off changes forever, and it is a near certainty that the next president, from whichever party, will be far more open to significant alterations.” In addition, the case of King v. Burwell comes before the Supreme Court this spring, and could gut not only federal subsidies but the employer mandate.

So while President Barack Obama intends to launch what is being billed as a charm offensive when he addresses Congress later this month, the new Republican leadership on Capitol Hill has unfinished past business on its agenda. The fate of Obamacare is increasingly grim, and if Republicans can put forward a convincing alternative, they can probably undo most of it, if not all of it. Democrats have no “Plan B” for the day Obamacare collapses. That presents the GOP with a unique opportunity for leadership.

Senior Editor-at-Large Joel B. Pollak edits Breitbart California and is the author of the new ebook, Wacko Birds: The Fall (and Rise) of the Tea Party, available for Amazon Kindle.

Follow Joel on Twitter: @joelpollak