Gilchrest came out of political retirement to share a personal view of the issue -- his brother David is gay and married to his longtime partner in Massachusetts. Gilchrest, who opposed changing the U.S. Constitution to ban gay marriage, argued that the unions should be allowed as a matter of "social justice, civil rights and a more viable democracy."

Britt, who met his wife while on a freedom ride against discrimination in public transportation in the 1960s, said he understands what it means to fight for equality. "Any couple in love should have the right to marry," he said. "Civil rights for gays and lesbians are just as important as civil rights for anybody else."