Having survived constitutional and political challenges, the implementation of the Patient Protection and Affordable Care Act in the United States is secure. On 6 November 2012, Democratic President Barack Obama was elected to a second term, narrowly but clearly defeating Republican Mitt Romney. Romney’s vow to “repeal and replace” the healthcare reforms known as “Obamacare” was a key aspect of his campaign. With Obama’s victory, millions of people will gain health insurance over the next decade, either through the private market or the expansion of Medicaid, a joint federal-state insurance program for people with low income or certain disabilities. In addition, the structure of Medicare, the federal insurance program for elderly and disabled people, should be retained.

The US presidential election was very close; a shift of several hundred thousand votes (out of more than 118 million votes cast nationally) in a handful of battleground states—including Florida, Ohio, and Virginia—could have given Romney the 270 electoral votes needed for victory, and, possibly, the power to block various aspects …