Jessica Alba naked and covered in tape? It's all part of a campaign to get young people to vote.

The actress is starring in an S&M-inspired public service announcement for Declare Yourself, a national nonpartisan, nonprofit youth voter initiative aimed at energizing young adults to register and vote in the 2008 election.

"Only you can silence yourself," the ad reads. "Make them hear you. Register to vote now…"

In the ad, she appears to be crying with shiny black electrical tape covering her mouth and naked body.

"I think it is important for young people to be aware of the need we have in this country to get them more active politically," Alba said, according to People magazine. "People respond to things that are shocking."

The dramatic image "really resonates" with the issue of voting, according to the 27-year-old star. "If you don't register and vote and make a difference, and hopefully change the bad things that are happening in our country, you are essentially just binding and muzzling yourself," she told People.

Alba was photographed last month in Los Angeles by Mark Liddell for the campaign, which launched in 2004 with Christina Aguilera and Jonathan Bennett.

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