by Akim Reinhardt
In the 150 years since the end of the U.S. Civil War, the Republicans and Democrats have maintained a relentless stranglehold on every level of American politics nearly everywhere at all times. While a handful of upstart third parties and independent candidates have periodically made waves, none has ever come close to capturing the White House, or earned more than a brief smattering of Congressional seats. Likewise, nearly ever state and local government has remained under the duopoly's exclusive domain.
Why a duopoly? Probably because of they way the U.S. electoral system is structured. Duverger's Law tells us that a two-party duopoly is the very likely outcome when each voter gets one vote and can cast it for just one candidate to determine a single legislative seat.
However, in order to maintain absolute control of American politics and fend off challenges from pesky third parties, the Democrats and Republicans needed to remain somewhat agile. The times change, and in the endless quest to crest 50%, the parties must change with them.
Since the Civil War, both parties have shown themselves flexible enough to roll with the changes. The Civil War, the Great Depression, and Civil Rights era each upended the political landscape, leading political constituencies to shift, and forcing the Democrats and Republicans to substantially and permanently reorient themselves.
Now, several decades removed from the last major reshuffling of the two major parties, we may be witnessing yet another major transformation of the duopoly as the elephant and the donkey struggle to remain relevant amid important social changes. The convulsions of such a shift are reflected in the tumultuous spectacle of the parties' presidential nomination processes.