Mark Sheldon Slackmeyer is a character in the comic strip '' Doonesbury '' . Mark starts out as a radical at Walden College , and leads several peace rallies ( in his first appearance , he referred to himself as " ' Megaphone ' Mark Slackmeyer " ) . The character was initially modeled after Mark Rudd , then in the news as a leader of Columbia University 's student protests of 1968 . Mark seized the office of Walden 's President King twice ( he considers the first time a failure as President King was far too cooperative ) , and in 1972 took a cross-country trip with Michael Doonesbury to Washington , and eventually to that year 's Republican National Convention in Miami , Florida
Republican National Convention
1972 Republican National Convention
Mark Slackmeyer