From www.scotusblog.com, it appears that Justice Kennedy sees both sides of the debate and could rule either way. He sees the concern with government being able to tell people what to buy, and he sees the concern of Congress seeing health insurance rates go up because young healthy people will not buy health insurance:
Later on, it would appear that Kennedy had some doubt about whether the health insurance market was, in fact, a unique phenomenon. But near the end of the entire argument, when challengers’ lawyer Michael A. Carvin was at the lectern, Kennedy made a comment that he may have started to see the issue differently.
To understand its significance, the context of this later remark is important. Justice Breyer had again, as he had done several times during the challengers’ argument, stressed that Congress was confronted with a situation in whch some 40 miliion people did not have insurance, and that gap was, in fact, having an effect on commerce that was substantial. “So,” Breyer said, “I thought the issue here is not whether it’s a violation of some basic right or something to make people buy things they don’t want, but simply whether those decisons of that group of 40 milliion people substantially affect the interstate commerce that has been set up in part” through a variety of government-sponsored health care delivery systems.
That, Breyer told Carvin, ”the part of your argument I’m not hearing.”
Carvin, of course, disputed the premise, saying that Congress in adopting the mandate as a method to leverage health care coverage for all of the uninsured across the nation.
Kennedy interrupted to that that he agreed “that’s what’s happening here.” But then he went on, and suggested that he had seen what Breyer had been talking about. “I think it is true that, if most questions in life are matters of degree,” it could be that in the markets for health insurance and for the health care for which insurance was the method of payment “the young person who is uninsured is uniquely proximately very close to affecting the rates of insurance and the costs of providing medical care in a way that is not true in other industries. That’s my concern in the case.”
That was the core of Verrilli’s claim about what Congress had confronted, and Kennedy had just phrased it — not as the government’s argument — but as his own perception. In both tone and content, it was a sudden change.