Four decades ago, Richard Nixon lived out the fantasy many liberals harbor about Donald Trump, stepping down in the face of possible impeachment over a slow-moving scandal long before his term was up. Before that happened, however, Nixon was reelected by a resounding margin, in large part because progressives made strategic errors that Democrats today appear hellbent on repeating.

In 1968, as in 2016, Democrats narrowly lost the White House after nominating a relatively moderate, establishment candidate instead of a more liberal alternative who had inspired a raging enthusiasm among younger voters. Democrats spent much of the next four years arguing about what direction the party should take. White working-class voters—traditionally a Democratic bloc—were sluicing away, and progressives, convinced the party needed to change both its policy direction and its coalition of supporters, demanded a new approach: a “loose peace coalition” of minorities, young voters and educated white Democrats, as strategist Fred Dutton wrote in his 1971 book, Changing Sources of Power. One year later, the party’s presidential nominee, the ultra-liberal Senator George McGovern of South Dakota, went on to lose 49 states in one of the most lopsided victories in American history.

http://www.politico.com/magazine/story/2017/10/09/democrats-mcgovern-1972-trump-nixon-2020-215687