Both sides involved in South Carolina's same-sex marriage debate are starting to rally supporters before the issue appears on the ballot in November - with a gay-rights group firing the opening shot by unveiling a billboard on I-26 last week.

The Alliance for Full Acceptance, a Charleston-based organization focused on achieving equality and acceptance for gay, lesbian, bisexual and transgender people, is paying more than $1,100 per week for the billboard, on westbound I-26 between the Rutledge Avenue and Spruill Avenue exits. It reads: "Someone you know, someone you love ... is gay. They need your help in November."

Warren Redman-Gress, the alliance's executive director, said the purpose of the message is to raise awareness of the upcoming vote, and to call on residents to take a stand against "discrimination."

"If South Carolina residents look into their lives, they'll see that there are people who they know and love who are gay, lesbian, bisexual and transgender, and those people need their support," Redman-Gress said. "There is an important vote in November, and those individuals will be drastically affected by that vote."

On Election Day, Palmetto State voters will decide if the state constitution should be altered to ban same-sex marriages. The unions already are prohibited under state law, but some groups argue that a constitutional amendment would offer stronger protection against the prospect of a judge's ruling forcing South Carolina to recognize same-sex marriages from other states.

In addition to the billboard, which will offer three messages before November, Redman-Gress said his group plans to mobilize support through direct-mail, radio and television ads, bumper stickers and other tactics. The alliance has 400 active members and a 1,300-person mailing list, and Redman-Gress said members say the constitutional amendment threatens more than the ability of same-sex couples to define their unions as "marriage."

"It's not simply an amendment about marriage," he said. "For us, it's a family discrimination amendment. It's saying that this state will recognize certain types of families, but other families paying the same amount of taxes won't be supported in any way."

Leaders with Columbia-based Palmetto Family Council, which promotes fundamental family values, said they are planning an active campaign to encourage people to vote to prohibit same-sex marriages. Executive Director Oran Smith said the council's advertising will celebrate traditional marriage while being respectful of homosexual friends and neighbors.

"We are encouraging people to vote yes for marriage as an institution between men and women," Smith said. "We all have friends who are gay and lesbian, but it's our belief that only opposite genders should be afforded the privileges associated with the term 'marriage.' "

Smith said he's not sure if his group will opt to pay for a competing billboard, as the council might decide to use smaller signs and display advertising instead. Still, he said he supports the alliance's right to use the billboard as a means of getting its message across.

"We expect to have a healthy debate about this issue," Smith said. "Let's present both sides to the people of South Carolina and see what they choose."

Reach Mindy B. Hagen at mhagen@postandcourier.com or 937-5433.