President Obama's healthcare law is under attack in the courts even as the administration sprints toward full implementation. Despite surviving a stiff challenge at the Supreme Court last year, some of the law's biggest provisions remain at risk from legal challenges. One set of lawsuits accuses the Internal Revenue Service of illegally implementing new subsidies to help people buy insurance. Separately, more than 60 lawsuits have been filed challenging the law's mandate for health plans to cover birth control. A loss for the administration on the contraception mandate would undermine a key selling point for the law that Democrats used to court women in the 2012 elections.