The Court that decided Loving was one of the most liberal of the 20th century. The Court that will rule on California's Prop 8 and the Defense of Marriage Act is one of the most conservative. Talking Points Memo's David Kurtz posted this chart earlier today, tracking the ideological rankings of the Supreme Court over the past few decades.

According to the data, the Court under Roberts right now is the most conservative it has been in 30 years.

That doesn't match public perception. A poll conducted by Pew Research indicates that 40 percent of Americans think the Court is balanced, though conservatives largely think it's liberal and liberals largely consider it conservative. (It's worth noting that TPM is a liberal media outlet.)

In other words, Americans, who largely support legalization of gay marriage, could be surprised by a more conservative ruling by the Roberts Court.

It seems likely that the trend toward acceptance of gay marriage will continue, as it did with interracial unions. But there will be holdouts. The map below shows those senators that have expressed support for gay marriage, a reflection of public opinion in the state. If the Court decides against overturning gay marriage restrictions, leaving decision-making to the states, it's likely that the last to ratify the practice will be some of those that were the last to embrace interracial marriage as well.