When covering elections, we generally argue that the presidential elections of 1964 and 1972 were catastrophic failures for, respectively, the Republicans and the Democrats. After all, each party's fringe nominated candidates that were not accepted by the electorate's moderates.
But David Broder reminds us that each candidate represented a wing within the party that was growing in strength and eventually allowed the party to dominate a series of elections. The Goldwater Republicans later fixated on Reagan. Now, he suggests, the wing that brought you George McGovern--who pushed to expand the party to aggressively include women and minorities--is deciding between Hillary Clinton and Barack Obama, two products of that inclusion.
He suggests that the effort to find strategic politicians that scrape through with narrow victories do not leave lasting legacies.