An infamous incident took place late in the campaign. McGovern was giving a speech and a Nixon admirer kept heckling him. McGovern called the young man over and whispered in his ear, "Listen, you son-of-a-bitch, why don't you kiss my ass?" The heckler confirmed this to an inquiring journalist and the remark was widely reported. By the following night, "KMA" buttons were being worn by people in the crowds at McGovern rallies. Several years later, McGovern observed Mississippi Senator James Eastland looking at him from across the Senate floor and chuckling to himself. He subsequently approached McGovern and asked, "Did you really tell that guy in '72 to kiss your ass?" When McGovern smiled and nodded, Eastland replied, "That was the best line in the campaign."

In the last week of the campaign, Henry Kissinger spoke of the ongoing Paris Peace Talks and said that "We believe that peace is at hand."McGovern angrily responded that Nixon had no plan for ending the war and that U.S. bombers would keep flying.

Final days