Pro-family supporters fear legalizing same-sex marriage will open doors for polygamy to continue breaking down the sanctity of marriage. The issue of polygamy, presented by many pro-family groups, is showing itself more and more as a dead end for pro-gay activists in their push for homosexual marriage to be legalized.

Tucker Carlson, host of CNN's "Crossfire", debated with Human Rights Campaign President Cheryl Jacques on the polygamy issue. Carlson asked her why shouldn’t polygamists be able to marry and all she could say was, "I don't approve of that."

President of Family Research Council Tony Perkins says, "The fact is that once you legally open the door for same-sex couples to marry, other groups will inevitably be clamoring for the same rights too.”

Peter Sprigg, senior director for the Family Research Council's Center for Marriage and Family Studies, concurred that if homosexual marriages were legalized, it’s only a matter of time before polygamists follow their footsteps. "It's not unlikely that if we get same-sex marriage, we will see a push for polygamy 20 or 30 years from now, if not sooner," he says.

Founder and host of syndicated radio program “Focus on the Family”, Dr. James Dobson listed six potential ramifications of legalized gay marriage during this broadcast Tuesday, which also included polygamy as the third ramification listed together with “other alternatives to traditional marriage."

Sprigg warns that it only takes some planning for a polygamy movement to happen.

"We have a large, well financed, 30-year-old social movement pushing for same-sex marriage," he says. "If polygamists were as well organized, as well connected in the media as homosexuals are, then we'd be seeing a push for polygamy too."

One thing is clear to pro-family advocates fighting to protect not only marriages but families: homosexual marriages must be rejected.

"Same-sex marriage would just be the ultimate nail in the coffin, so to speak, on the concept that sex, childbearing, and marriage should all go together," Sprigg says.