At a recent training session on social media attended by grassroots conservative activists, Austin James of American Majority encouraged conservatives to give low ratings to books about President Obama on Amazon.com and to write reviews that aim to dissuade users from buying the books -- or buying into Obama's ideas.

James spoke Friday about engaging in "guerrilla warfare" against liberals online at Americans for Prosperity's "Defending the American Dream Summit," where conservatives cheered when Chicago lost its Olympic bid. Americans for Prosperity has been a key force in trying to channel the anti-Obama vitriol into a viable political movement through efforts such as tea parties.

"What if I went to every Obama book I could find and I went 'one star, one star, one star?'" James asked the crowd. "I mean, 80 percent of the books that I view and put stars on online, I never read, people. That's just how it works."

This wouldn't be the first time activists have tried to game a social media site in an attempt to skew the conversation in their favor. Last year, the deluge of political stories on Digg.com's homepage led the popular news-aggregating site to devote an entire section to politics.

Abusing the user review tool on Amazon might already be happening. Though it's impossible to verify if commentors have read the books they're writing about, it's clear that people from across the political spectrum are already using the forum as a platform for sharing their views. Amazon user Sylvana Dallacqua, for instance, gave The Audacity of Hope one star and wrote, "We all need to know what this president's goals are, the worst of which is the dismantling of our Constitution."

For its part, Americans for Prosperity does "not endorse or support" the practice of artificially lowering a book's rating, said spokeswoman Mary Ellen Burke. "The great thing about the Internet is the exchange of ideas, and voting down a book that you haven't even read doesn't, I don't think, promote an exchange of ideas," she said.

But James told NationalJournal.com that it's all in the interest of achieving balance on the Internet, where, he said, liberals "greatly outnumber" conservatives. "Sometimes you do have to resort to those kinds of tactics when you go online and you see Obama merchandise and T-shirts and books and things all over the place," he said, "because there are so many people who do rate them 5 stars because they're a fan of Obama."

Such a strategy might make an impact in the online marketplace -- if not in public opinion -- many studies have shown that most individuals find customer reviews to be extremely important in determining what they purchase.