As they prepare to nominate Mitt Romney as their presidential candidate for the November 6 election, Republicans have added language to their official platform that anti-smut activists said would encourage the federal government to step up prosecution of pornography involving adults.

"Current laws on all forms of pornography and obscenity need to be vigorously enforced," the platform says, according to a draft obtained by Reuters. Republicans are planning a Tuesday vote on the document, a nonbinding statement of principles that tackles everything from monetary policy to abortion.

Though previous Republican platforms have called for increased prosecution of child pornography, this appears to be the first time that the party has called for a crackdown on sexually explicit material involving adults - a multi-billion-dollar industry.

Obscenity has been notoriously difficult to define in a legal context. The Supreme Court in 1973 held that to be obscene, material must depict sex in a manner that offends contemporary community standards and is devoid of artistic or scientific value.

Adult obscenity cases have been exceedingly rare over the past 20 years. Though the administration of George W. Bush promised a crackdown, only the most extreme forms of pornography have been targeted.

Anti-pornography activist Patrick Trueman said the language in the Republican platform would bolster a broader push against the type of sexually explicit material that is sold by convenience stores, by hotels via pay-per-view television programming, and satellite and cable TV providers.

The widespread availability of Internet pornography has made it harder for a generation of young men to find intimacy with their wives, he said.

"It's a growing problem for men in their 20s," Trueman said. "It's changed the way their brain maps have developed. This is the way they get sexually excited."

According to Trueman's group, Romney promised earlier this year that he would push for "strict enforcement" of obscenity laws, as well as the broader use of blocking software to screen out Internet porn.

Trueman and other social conservatives criticized Romney during his 2008 bid for having served on the board of directors of hotel operator Marriott International (MAR.N), which sold sexually explicit content in its hotel rooms. Marriott announced last year that it would gradually stop providing pay-per-view "adult" material.

The Internet research firm TopTenReviews estimated that adult pornography revenues through magazines, the Internet and video sales and rentals totalled $9.4 billion in 2006. (Editing by Leslie Adler)

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