It may not exactly be rapid response, but I don't know of anyone else who's done something like this -- even people who can walk:

Pro-Kerry group confronts author of 'Unfit for Command'

CHICAGO - The battle over John Kerry's Vietnam War record flared up in Chicago Tuesday, when members of a fledgling group that supports the Democratic presidential nominee confronted the author of an anti-Kerry book at a downtown luncheon.

At one point, the bickering became so intense that organizers called in police. No arrests were made, but the book signing and speech, sponsored by the City Club of Chicago, was punctuated with sharp exchanges between author John O'Neill and members of a group called truthandtrust.com....

As O'Neill autographed books for admirers, veteran Bobby Muller approached in his wheelchair, shook the author's hand, then asked repeatedly if O'Neill would debate him on Kerry's record.

After the two bickered for a few moments, O'Neill's wife, Anne, intervened, telling Muller to stop while nudging him away in his wheelchair....

Organizers called in security and threatened to throw Muller out, but he was allowed to stay for the luncheon. Several times during O'Neill's speech, Kerry supporters in the audience jeered or shouted "that's not true" as O'Neill laid out the basis of his book.

Later when former Swift Boat captain and Kerry supporter Skip Barker asked a question, O'Neill dismissed him and others as Democratic Party plants....

--Chicago Tribune/Kansas City Star

Do you know who Bobby Muller is? He took a bullet in Vietnam and now he's a quadriplegic, but, as The Boston Globe's Michael Kranish explained in 2003, he's done some good:

... after graduating from law school, Muller devoted himself to securing more benefits for veterans. Muller, Kerry, and two other veterans cofounded Vietnam Veterans of America. "As far as I'm concerned, Bobby Muller is one of the great heroes of the veterans' efforts in the country," Kerry says.

When Time magazine in August 1979 compiled its list of 50 future US leaders, it picked Muller...

In the 1980s,

Muller took a trip to Cambodia that changed his life once again. The country was filled with victims of genocide, including many left limbless by land mines. After so many years focusing on US veterans, he was increasingly concerned about victims of war everywhere. He started by setting up an organization to provide prosthetics to Cambodians. Then, concerned about the millions of land mines still buried around the world, he worked to establish a campaign to ban land mines. The campaign seemed quixotic, but several groups signed on to the cause, and Muller hired an activist named Jody Williams to help run the operation, which would later be called the International Campaign to Ban Land Mines. Muller's veterans foundation would eventually spend $5 million on the effort....

One day in 1997, a representative of the Nobel Peace Prize called Muller with the news: The Nobel had been awarded to the International Campaign to Ban Land Mines, with Williams as a co-recipient. Muller wasn't named in the prize. Kerry, like many friends, regrets that Muller was not singled out. "In my judgment, Bobby Muller was one of the co-winners of the prize," Kerry says. "If there could have been a way for him to be named also, he should have been."...

Oh, and Muller's been immortalized in song:

...his work for Vietnam veterans eventually landed him in the orbit of Springsteen.... Springsteen helped save Muller's organization [with a 1981 benefit concert]....

A couple of years later, Springsteen began thinking about a song titled "Born in the U.S.A.," a dark and deep tale about a recruit going off to war. The disillusioned vet comes back with "nowhere to go . . . I'm a cool rocking daddy in the U.S.A." Springsteen later confirmed in a television interview that Muller was the man behind the phrase.

Here's the Truth & Trust site.

(Via Letter from Gotham, where you can read the whole Tribune article, which requires registration.)