Arlington, Va. (CNSNews.com) - Human cloning, whether for reproductive or therapeutic purposes, is the most critical social issue of our time, two conservative lawmakers told participants gathered in Arlington, Va. for the Conservative Political Action Conference (CPAC).

"We need your help" in getting a Senate bill passed that would ban human cloning, Sen. Sam Brownback (R-Kan.) implored the crowd. The House passed Rep. Dave Weldon's (R-Fla.) companion bill last year, which President Bush has said he would sign if and when the Senate passes it.

Brownback and his House colleague and fellow physician Weldon described the ethical issues of cloning in dramatic terms, with Brownback calling it the "key social issue" of our time and a "watershed time for humanity." Weldon called it "human experimentation of the worst kind."

"What we do here is critical," said Brownback, because the rest of the world is looking to the U.S. for guidance on this issue.

The duo also urged the activists to cut through the terminology used by pro-cloning advocates who try to draw a distinction between reproductive cloning and so-called therapeutic cloning, which is used for stem cell research that may some day produce cures for human diseases. "All cloning is cloning"-that's the bottom line, said Weldon.

In both cases, he explained, a human embryo is produced from the cloning process, the only difference being the purpose for which it's used.

Weldon also warned of health and other ethical problems associated with human cloning. "Of all the species that have been cloned so far, there has been evidence that all of the offspring have genetic abnormalities," he said, such as the cloned sheep Dolly developing arthritis at a young age.

The offspring are also often abnormally large, said Weldon. "A woman trying to give birth to a cloned human could appear nine months pregnant when she's only four-and-a-half months along."

Brownback and Weldon believe there is momentum behind their cause because many conservative and liberal groups are united on this issue. And both camps share a concern that a market for human eggs will prompt low-income women, perhaps college students, to undergo risky and exploitative surgery for money.

The drugs that are used to generate the volume of eggs necessary for cloning purposes has been shown to slightly increase the risk of ovarian cancer, according to Weldon.

"It's one thing to be exposed to this drug because you really want to get pregnant and have a baby," he said, but "it's a totally different issue ethically and morally when you start talking about giving this drug to women so they can make $3500 or $5000 to help pay for their college expenses."

Brownback indicated that an important tool for anti-cloning forces may be a newly discovered adult human cell that is pluri-potent, able to take the form of other types of cells. We don't even need clones in the search for cures to disease, he said.