5 possible outcomes of the Supreme Court Prop. 8 case

The Supreme Court has the opportunity to issue a landmark ruling this year as it considers the constitutionality of Proposition 8, California's ban on same-sex marriage.

It could define same-sex marriage as a constitutionally-protected right, or it could uphold the ban, setting back the gay rights movement for years. The case, however, isn't as simple as deciding whether or not same-sex couples have a right to get married.

After the Supreme Court today hears the oral arguments in the case Hollingsworth v. Perry, it has five options to choose from. Below is a rundown of the court's choices -- whether to protect the right to same-sex marriage in 50 states, zero states, nine states or one state. There's one last option -- to punt on the decision and dismiss the case.

Same-sex marriage constitutionally protected, nationwide

In the most dramatic ruling it could deliver, the Supreme Court could use Hollingsworth v. Perry to rule that marriage is a constitutional right available to all Americans, gay or straight.

"The Prop. 8 case has the potential to be the Brown v. Board of Education for gay rights," UCLA School of Law Prof. Adam Winkler told CBSNews.com.

"The question is whether the court's ready to do that," said Walter Dellinger, a partner at O'Melveny & Myers who served as U.S. Solicitor General during the Clinton administration.

Dellinger noted that such a ruling would be a much larger leap than the court has taken in the past in comparable cases. For instance, when the court issued the 1954 Brown v. Board ruling, there were 17 states that mandated segregation in schools. In its 2003 Lawrence v. Texas decision, the court invalidated sodomy laws in 13 states. By contrast, there are currently 39 states with constitutional or statutory bans on same-sex marriage.

"There's reason to think there may not be five votes" for that kind of ruling, Dellinger said.

While proponents of same-sex marriage -- traditionally aligned with Democrats -- want the court to make this move, Dellinger said, "Ironically, politically nothing would be better for the Republican Party than for the court to go all the way, which would take the issue out of politics."

The issue has turned from a wedge issue for Democrats into a growing problem for Republicans as public support for same-sex marriage builds.