The formation of our present two party system has been long in the making, but I truly believe that it's metamorphosis is far from complete. Like our Constitution, which provides the framework for changes in our social structure, (not, as some assume, a concrete code of what it must remain), our political structure allows for an ever-changing landscape of ideas and cultural shifts.
Indeed, in the first few hundred years there were many political parties formed and abandoned as our nation grew into, and then out, of them. As social pressures came to bare, coalitions of mutual cause came into existence, rose to power, and then when the wrongs had been addressed, they faded away or were absorbed by other factions.
This ongoing process of reactionary political growth ended around 1854, with the formation of the Republican Party.
The northern states, at that time, were against slavery, morally, and as a means of commercial growth, and a coalition was formed between many of the factions of the day in reaction, specifically, to the Kansas–Nebraska Act, which repealed the Missouri Compromise by which slavery was kept out of Kansas.
Unlike third parties of today, it wasn't just folks sitting around in someone's living room agreeing with the fact that no one was voicing their concerns, and then drafting one of their own to run in an election; it was a concerted effort by citizens AND those already in Congress, and state and local legislatures, to branch out and challenge the existing political structure in an effort to demand redress of their grievances
This is also in contrast to the formation of groups such as the Tea Party, which is nothing more, (now), than a wing of the Republican Party, or other such groups that are a part of, or have been swallowed up by, both existing parties. If there were to be such an entity formed today, it would possibly include figures such as Senator Warren, Senator Sanders, Senator Brown, Governor O'Malley, and Representative Alan Grayson of Florida.
It would have it's initial setbacks, such as the defeat of John C. Freeman, the first Republican Presidential candidate, in 1856. But by 1860, a new fresh face in national politics, Abraham Lincoln, was elected President by the party which took it's name to show opposition to the aristocracy and corruption that dominated Washington at the time. (My, but how they've come full circle.)
With the overwhelming majority of citizens today, of BOTH parties, supporting the same issues, such as no TPP, voter rights, health care, less war, fair taxation, an end to corporate welfare, repeal of Citizens United etc., and even more who have dropped out of their civic involvement completely, it is time for the formation of a new political party.
A truly populist party, led by those with a record of standing up for, and willing to pledge to, those issues that the American people TODAY hold as the social and moral values we all agree on, rather than the SOS of false division, fear-mongering, and fleecing of our labor to support a government that no longer pays heed to our wants, needs, and aspirations.