SAN FRANCISCO -- Pacific Gas & Electric is removing Facebook comments criticizing its push for a California ballot initiative limiting utility competition.

Facebook -- which has 400 million users and is the second most-popular U.S. website -- has emerged as a political tool, with candidates at all levels setting up pages to rally supporters. PG&E is among them.

The utility has a page for its Proposition 16 initiative, which would require local governments wanting to embark on a public-power program to win two-thirds of voter support. The page, which requires users to register their approval for Prop 16 before they comment, has 34,473 "fans."

"It is not a scam to maintain a monopoly simply by giving people the opportunity to vote on an issue," one commenter wrote. "I still need to read all the fine print but I am swaying toward a yes."

Wrote another: "I want my local government to convince me they should go into this enterprise. So far I am not convinced due to the inability to fix roads, keeps parks and libraries open, and police on the streets."

Over a 12-hour period last week, E&E observed the removal of six comments, some within minutes. One of those was linked to an article from the San Francisco Chronicle, which reported PG&E was the sole financial backer of the $35 million campaign until the California Chamber of Commerce donated $91,000. Another posting by a city council member in Fort Bragg said, in part, "This proposition is funded by PG&E and is an example of misleading information! ... This is just another cynical ploy by a giant corporation."

Censoring a Facebook page is not illegal. The creator of a page has control over its content, within limits on profanity, harassment and abusive language.

"I think it's more of a PR question," said Rebecca Jeschke, a spokeswoman for the Electronic Frontier Foundation, an Internet free speech and privacy rights watchdog group. "Constituents will be angry when they see their comment's been deleted. Is this a good idea, PR-wise, to be treating Facebook commenters like this?"

Robin Swanson, a spokeswoman for the Prop 16 campaign, defended her actions. "Just like anybody can remove comments from a Facebook page, we'll use our discretion to remove comments," she said. "We don't have to justify what we put on our Facebook page. This is our Facebook page."

Censoring Facebook comments isn't likely to hurt PG&E's chances, said Steve Maviglio, a longtime Democratic operative who is managing a campaign against a ballot initiative that would suspend California's climate law. "The people who are posting opposing comments are already in the enemy camp," he said.

But the micromanaging needed to keep the page on-message might be too labor-intensive to make it worthwhile, he said. For example, he said, California Attorney General Jerry Brown, a Democrat running for governor, has had his page inundated in recent weeks with demands to prosecute Michael Jackson's doctor for murder.

"This is a new headache for campaigns," Maviglio said. "The thing about Facebook is, it's a wide open forum for anybody; you run the risk, when you use it, it's not going to be completely positive. On one hand, I don't blame them at all, but on the other hand, it's impossible to manage."

But to users, the practice of censoring comments seems unethical. Bill Kimberlin, a film editor from North Berkeley whose comments were purged from the PG&E site, complained to the California Public Utilities Commission and found he had no recourse.

"I think it's a little outrageous in the world of the open Internet, based on your proposition that people should have a right to vote, that if I go on there and say anything, you immediately throw me off," he said. "If corporations or others are using something that has 400 million members to put out a story and then not allow any response from anyone unless it's positive to them, that's at least something that's worth letting people know."