And O'Brien was here in this north central Montana rail town last week when Burns strode into the Duck Inn for a luncheon appearance. "Hello, Kevin!" Burns boomed across the room.

"He's with the Democrats," Burns explained to the small crowd. "Everywhere we go, he goes." The 24-year-old, baby-faced O'Brien is a "tracker" a videographer who follows an opposing candidate, hoping for a gaffe, an awkward moment, a bit of hypocrisy or inconsistency that could be campaign fodder.

Trackers using inexpensive hand-held cameras and having the ability to post clips almost instantly on YouTube and other video-sharing websites have become a major element in several campaigns. The most notable tracker moment this year came in Virginia when Republican Sen. George Allen used the word "macaca" to describe his Democratic tracker, a 20-year-old Indian American man.

Allen's critics say the word was a racial insu Allen says it was a "made-up word" that intended no offense. The senator nonetheless apologized, and the issue dominated news coverage of the campaign for days. In some ways, the work of trackers is not new.

Opposing campaigns have long followed what the other guy was saying, trolling for a slip or worse. In 1987, for instance, Sen. Joseph R.

Biden Jr.'s presidential campaign was torpedoed when opponents unearthed the Delaware Democrat's use of bits of speeches lifted from other public figures. But back then, opposing campaigns had to either persuade the news media to pick it up or invest in a campaign ad to get their message on the air, said Michael Cornfield, vice president at ElectionMall.

com, a nonpartisan campaign-technology firm. With YouTube and related technologies, publicizing material now is much less cumbersome and less expensive. "In the past, people were assigned to shadow campaigns and had cameras or tape recorders, but they never had a way to instantly post what it is they came up with," said Cornfield, who is also an adjunct professor of political management at George Washington University.

Although candidates of both parties post their television advertisements on YouTube, the Democrats appear more inclined so far to use the technology. In the Montana race, Republicans have periodically tracked appearances of Burns' Democratic opponent, state Senate President Jon Tester. But the GOP has posted only one: a recent call by Tester to repeal the Patriot Act.

"It's fair to say that their campaign is more into YouTube than ours is," said Jason Klindt, a Burns spokesman. Several of the Burns moments captured by O'Brien have worked their way into the Montana news cycle and fed discussion about Burns' reputation for verbal miscues and worse. In the past, the senator has apologized for using racial epithets.

According to YouTube, video of Burns getting sleepy taped by O'Brien on his Sony Handycam camcorder and dubbed "Conrad Burns' Naptime" has been watched more than 75,000 times. : L.A.

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