After two days of intense and nuanced debate within the halls of the U.S. Supreme Court, supporters of gay marriage certainly have cause for optimism.

On Wednesday, for the second day in a row, the line of questioning suggested the high court is at least skeptical about the constitutionality of laws that prevent same-sex couples from marrying and from enjoying the same federal benefits as heterosexual couples.

The focus was the Defense of Marriage Act, passed by Congress in 1996, which prevents legally married gay couples from receiving the same federal benefits — tax breaks, survivor benefits, health insurance, etc. — as other married couples. Same-sex marriage is legal in nine states and the District of Columbia.

The central question was this: Does the U.S. government have any rational basis for denying benefits to legally married gay couples?

The majority seemed to concur that the answer is no.

Justice Anthony Kennedy, considered the court's swing vote, suggested that DOMA was in conflict with the traditional right of states to "regulate marriage, divorce, custody.<TH>.<TH>."

A day earlier, the focus was on California's Proposition 8, which voters approved in 2008 rescinding marriage rights for same-sex couples. There again, the justices appeared dubious about overturning lower courts that already found the initiative to be unconstitutional.

Nevertheless, supporters of same-sex marriage should not set expectations too high. While it's possible-to-likely that the high court will overturn all or part of DOMA, the possible outcomes for the Proposition 8 case are many and varied.

One of the least likely scenarios is that the court would use the Proposition 8 case as an opportunity to offer a blanket endorsement of the constitutionality of gay marriages and expand same-sex marriage rights to other states beyond California.

A more likely scenario would be a narrow ruling that finds the initiative unconstitutional because it denied rights already granted by the state Supreme Court.

A more disappointing outcome is one that appeared to be favored by Chief Justice John Roberts, who repeatedly raised doubts as to whether the plaintiffs in the case had proper standing to file the appeal and whether the Supreme Court should have accepted the case at all.

In any case, given the tortured rationale and arguments by attorneys defending Proposition 8, it seems inconceivable that the court would conclude that there's breathing room within our nation's constitutional promises of equal protection under the law for such discriminatory measures as Proposition 8 and DOMA.

Theodore Olson, a lawyer for two same-sex couples who are challenging the law, said it best on Tuesday in opposing Proposition 8. "This is a measure that walls off the institution of marriage, which is not society's right," he said. "(T)his court again and again and again has said the right to get married, the right to have the relationship of marriage is a personal right. It's a part of the right of privacy, association, liberty, and the pursuit of happiness."