Well Lilo, so many SCOTUS opinions are a function of the majority's ideology. Take for example the Heller opinion regarding the gun ban in DC. It wasn't until one of the last few pages of that opinion that Scalia referenced Oringinal Intent. The rest of the opinion consisted simply of historical references.

While the individual mandate may not have precedent, it could reasonably derive it constitutionality from the Elastic Clause or the "general welfare" provision of Article I, Section 8.

And by the way, cases are not forwarded to SCOTUS; they are solicited through the "rule of four" and certiorari. If the case gets there and Justice Kagan recuses herself, then a tie vote will leave it with the 11th circuit court opinion.