The NYT explains the group as such:
[The] American Bridge 21st Century...[is] a new Democratic organization that aims to record every handshake, every utterance by Republican candidates in 2011 and 2012, looking for gotcha moments that could derail political ambitions or provide fodder for television advertisements by liberal groups next year.The idea of tracking political opponent's every move really erupted into the mainstream when a Democratic tracker captured Senator George Allen of Virginia calling him "macaca" - which critics alleged was meant as a racial slur. The gaffe derailed Allen's re-election campaign and demonstrated the true power of trackers:
But the point is not only to capture gaffes on camera. The video that these trackers take is accompanied by a detailed, time-coded "field report" that will be put into a searchable database that will be used to index the hours of video. Campaigns will be able to use this video and will have hours of footage of candidates explaining their views.
The New York Times explains,
If a Democratic group is ever looking for the image of Mr. Romney paying for a 25-cent lemonade with a $5 bill, it will know just where to go. If it wants a clip of Mr. Romney saying the president has made the economy worse, the archive will have one. Or if it needs Mr. Romney talking about World War II veterans, it will be able to find it.American Bridge is the creation of David Brock, who also established Media Matters, a popular website among progressives which critiques channels like Fox News. Brock is a convert to the Democratic Party, spending much of his time in the 90s writing blistering attacks directed towards former President Clinton. He was largely seen as a predecessor to Matt Drudge, who has become wildly famous with the Drudge Report. Now working for the Democrats, Brock and American Bridge have raised several million dollars and hope to bring in around $15 million to establish the organization as a vital piece of the liberal political infrastructure.
“I can come up with the spin. I need the facts,” said Paul Begala, a former top adviser to President Bill Clinton and a senior strategist for Priorities USA Action, an outside group that is working to re-elect President Obama. Mr. Begala said American Bridge would help fuel his group’s ads. “Let’s go to the videotape!”
The story is not long and at least to me, it's extremely interesting to read about people who track for a living.
The full story can be accessed here or with this link:
http://www.nytimes.com/2011/07/09/us/politics/09trackers.html?pagewanted=1&_r=1&emc=eta1