"In 1970, George Mcgovern, the way-long-shot antiwar candidate, began to experiment with the novel political fund-raising technique of direct mail to finance his unlikely primary race.
This political marketing strategy, according to an article that appeared in New York in September 1972, was the brainchild of Morris Dees, who would become among the most prominent southern liberal activists but who was then the head of a publishing company that sold special-interest books through the mail.
The idea—born not so much from marketing brilliance as from a lack of fund-raising alternatives—was to use the mail to solicit people who had already identified themselves as likely McGovern partisans. It was the method, not the goal, that was new—after all, politicians are always looking for help from their core supporters.
But the method introduced a heightened efficiency into the process. Almost all of the mail sent by the McGovern team went to three groups. You got a solicitation if you subscribed to liberal magazines: The New Republic, The New York Review of Books, Ramparts, or Bulletin of the Atomic Scientists, for instance. If your name appeared on lists maintained by organizations like Americans for Democratic Action or the ACLU or Zero Population Growth, you got a letter. Or if your name and address had been among the hundreds of thousands collected over the years of the antiwar movement (perhaps you had contributed to the campaign to support the end-the-war McGovern- Hatfield Amendment), you got a sincere, well-crafted, multipage pitch from the McGovern marketers.
While this selective approach sounds obvious and, indeed, toothless from the current overmailed, overtargeted vantage point, it was revolutionary at that moment, producing the lion’s share of the McGovern campaign’s funds and enough cash to overwhelm the other Democrats in the race."
the article goes on to quote Lester Wunderman, two months before the McGovern Debacle
“They’ve revolutionized the political process with this campaign,” said Lester Wunderman, one of the fathers of direct mail, about the McGovernites, two months before disaster befell the campaign. “You see, direct mail is essentially a populist medium. Put it to work the way they have and you have really created participatory democracy on a level that was never before contemplated. And because it opens up the possibility for real dialogue—in a way that television can never do—it’s a twentieth-century hustings.”
http://www.newyorkmetro.com/nymetro/news/media/columns/medialife/n_9188/