03/29/2012 06:22 pm ET Updated May 29, 2012

Obama's Odds of Winning the Health Care Ruling: 37%

It is both customary and folly for Supreme Court watchers to predict outcomes of Supreme Court cases based on oral argument. So let me engage in the customary folly.

The argument could hardly have gone better for the opponents of the Affordable Care Act. Paul Clement, the lawyer for the 26 states challenging the Act, was masterful, offering the best oral advocacy at the Court in decades. Solicitor General Donald Verrilli fought gamely, but was over-matched and seemingly under-prepared. From the start of Tuesday's key argument when he flubbed his opening and grasped for a glass of water, until Wednesday afternoon when he could not articulate a single hypothetical example of when federal government spending conditions would be coercive on states, Verrilli left those of us who believe in the constitutionality of the ACA with a pit in our stomachs. I kept shouting better answers at my audio player, and I am sure I am not the only one with such a response.

So should we abandon hope?

Members of this Court often make their views known by the tone of their questions. After listening to the arguments, and using the substance and tone of the questions as a guide, there are only two votes in play on the two main constitutional questions: Chief Justice Roberts and Justice Anthony Kennedy.

The four Democratic-appointed Justices (Ginsburg, Breyer, Sotomayor and Kagan) are safe votes on both the individual mandate and on the Medicaid extension. On the other side, Scalia, Thomas, and Alito are safe votes to strike down the individual mandate as beyond the commerce and taxing powers. Moreover, it sounded to me that those three are even willing to strike down the Medicaid extension as beyond the government's spending powers. (Even though Thomas did not ask questions, as is typical for him, his prior opinions leave no doubt as to his vote.)

Both Kennedy and Roberts, however, asked pointed questions to both sides, on both constitutional issues. In fact, at several points Chief Justice Roberts did a better job of articulating the government's position than Verrilli.

Nevertheless, I would put the odds of Roberts holding in favor of the government on the individual mandate at probably 1 in 3, and on the spending clause at 1 in 2. Kennedy is tougher to guess, but probably no better than 1 in 3 on either question.

What does that say about the outcome? Remember for the opponents to win on either question they must get BOTH Kennedy and Roberts. But for Obama to win a total victory he has to win BOTH questions.

So play out the probabilities. (Again, I recognize this is folly. But humor me.) For Obama to win the individual mandate question, he has a 1/3 chance of getting Roberts and 1/3 chance of getting Kennedy. So that means he will get one of them -- and win -- about 56 percent of the time. (ACA opponents get Roberts 66 percent of the time; in 66 percent of those instances they also get Kennedy. They need both to happen. That means they win only 44 percent of the time.)

On the spending power, the odds are even better for Obama. Opponents get Roberts 50 percent of the time; they get Kennedy 66 percent of the time. They get both, then, only 33 percent of the time. In other words, Obama wins the spending clause question 66 percent of the time.

Not bad odds, considering how poorly the week went for the president.

But wait. For Obama to claim a complete victory, he must win both questions. If he wins the commerce clause question 56 percent of the time and the spending clause question 66 percent of the time, he'll win both about 37 percent of the time.

So don't bet the house.