Anyone who has been reading Kathleen Sebelius' profile on Wikipedia has a right to feel confused. For much of the two years that the Kansas governor has been listed in the popular online encyclopedia, Sebelius' entry has noted that she "is known for her support for gun rights." Then, on February 22, the wording suddenly changed to say that Sebelius "is not known for her support for gun rights."

Did Sebelius suddenly reverse her views on gun control? Not exactly. What happened is that a gun-rights supporter disagreed with the way Sebelius' views were being portrayed. So he did what anybody with a computer can do on Wikipedia: He edited the entry. Using the alias "Saltforkgunman," the advocate changed only a few key words. But by the time he was done, Sebelius' profile played up the fact that she had vetoed a concealed-carry bill.

Had this tiny word skirmish taken place in some obscure corner of the Internet, it wouldn't much matter. But Wikipedia is now one of the most popular Web sites in the world, with more than a million articles on subjects from politics to sports to pop culture. Search "Kathleen Sebelius" on Google--or the name of any governor or big-city mayor-- and a Wikipedia profile will be one of the first items you'll see. Going into the 2006 elections, this uncensored free-for-all is, for better or for worse, an information source that many voters will find authoritative.

Wikipedia calls itself an encyclopedia, but the site is more blog than Britannica. The point of the wide-open editing policy is to amass in one place the collective knowledge of thousands of people. The upside is timeliness: Wikipedia entries are updated continuously, sometimes several times a day. The downside is that volunteer writers, caught up in the passion of current events, frequently violate Wikipedia's golden rule about writing from a neutral point of view.

That's especially true when it comes to politics. Wikipedia profiles of politicians have become battlegrounds for spin doctors, hacks and people pushing agendas. In February, Wikipedia administrators blocked some users in Washington, D.C., with Capitol Hill Internet addresses from making edits. Allegedly, congressional staff had been burnishing their bosses' profiles and deleting unflattering facts.

Is the same thing happening in statehouses and city halls? A Wikipedia spokesperson says he's unaware of instances where state or local Internet addresses have been blocked for making improper edits. Still, there's no question that bias has a way of creeping into the entries of high-profile pols.

For example, the Wikipedia profile of Texas Governor Rick Perry has a section devoted to "Perry-isms." It's true that Perry, like any politician, has had his share of gaffes. But is the fact that he once told a reporter, "Adios, Mofo," something that really belongs in an "encyclopedia" entry?

Pranksters also enjoy defacing Wikipedia articles and using the site to spread rumors. One day recently, the photograph of Utah Governor Jon Huntsman Jr. was swapped out for the cartoon likeness of Buzz Lightyear. Volunteers regularly police Wikipedia for vandalism. The offending picture was removed almost immediately.

The real battle for the soul of a Wikipedia profile, however, is a more subtle matter of word choices and tone. Phrases in Sebelius' profile, for example, sound like they were lifted from her press releases. "She has been applauded by Democrats and Republicans alike for her responsible economic policies," it says. The much-edited section on gun control is a bit murkier. "My bag is putting the facts in where they belong," Saltforkgunman said in an e-mail response to my queries.

Two weeks later, however, an anonymous user scrubbed the Sebelius profile yet again. Now it reads: "While a responsible hunter herself, she vetoed, like her Republican predecessor, a concealed-carry law that would have allowed guns to be carried into the Statehouse, Churches, and private establishments against the wishes of the property owner."

Of course, that's what Sebelius' entry said when Governing went to press. By the time you read this, it will most likely say something else.