By Jericka Duncan

PHILADELPHIA (CBS) — They say they’re fighting for marriage equality.

Protesters rallied in D.C on the same day that the Supreme Court listened to arguments on whether California’s Proposition 8 ban on same-sex marriage is constitutional.

“When you’re grown, you do as you feel,” said Gail Campbell of Wilmington. “I don’t have a problem with it.”

Right now, nine states have legalized same-sex marriage. Delaware Governor Jack Markell says Delaware could be number ten.

“Our legislative session ends in June,” said Gov. Markell. “I’d say at this point, there’s a good chance a bill will hit my desk. I can’t be certain with how the legislation goes.”

In 2011, Gov. Markell signed the Civil Union and Equality Act into law, giving same-sex couples the same rights as those who are married.

“It’s a full indication, in terms of the court of law, that you are treated exactly the same as everybody else,” he says.

While the public’s opinion about same-sex marriage has changed over the years, there are still a number of people who believe marriage should be between a man and a woman.

“I think it’s an abomination of the body that God gave you,” said Barbara Drake. “It’s abusive, it’s not natural, it’s just — so many things wrong with it, to me.”