"It's been an incredible experience and turned out to be a historic one," said Kris Perry.
Perry and Sandy Stier are one of the two couples behind the lawsuit challenging Proposition 8 -- California's ban on same-sex marriage. Since the measure's passage in 2008, polls show public sentiment has dramatically shifted.
Even President Barack Obama now supports marriage for the nation's gays and lesbians and his administration has filed a brief on their behalf with the U.S. Supreme Court.
"If we're successful and we prevail, and no lower court rulings are reversed and Proposition 8 goes away, that was our goal. We will have reached our objective. It will also send a message to the rest of the county," said Perry.
But it will not change the minds of critics like Bill May, from Catholics For the Common Good, who campaigned on behalf of Prop 8.
"It's not about same-sex marriage. It's the question of whether marriage should be redefined to eliminate the only institution that unites kids with their moms and dads," said May.
"We're not trying to redefine marriage. We're trying to have access to marriage and that's what it's all about. It's just equal access to an institution that clearly the American society holds dear," said Stier.
This Berkeley couple, parents of four sons, says they feel a sense of honor and responsibility for their role in this historic case. It's unclear if the justices will rule narrowly just on California or make a 50-state decision. Both sides are optimistic.
"We are very confident the court will uphold the will of the voters to define marriage between a man and a woman," said May.
The justices are expected to rule by the end of June.
ABC7 News reporter Carolyn Tyler is traveling to Washington D.C. where the Supreme Court will consider whether California's Prop 8 wrongly denies gays and lesbians the right to marry. Her reports will begin on Tuesday.
In a side note, America's top pediatrics group is coming out in support of same-sex marriage. The American Academy of Pediatrics said nurturing couples in a marriage gives children raised by same-sex couples a feeling of permanency and security. According to the group, it's the same advantage the children of straight couples get when their parents are married.