The huge difference between today’s political world and the political world of the mid-19th century is that today the parties goes all the way down.
The rise of political machines in the classic sense occurred in dense, poor, crowded, rapidly growing cities in the northeast. There were few to no municipal services provided through taxes so political clubs arose to provide jobs and food and fuel and other basics to the poor in exchange for votes. Those votes could be parlayed into money through graft. This mostly happened after the Civil War, because most industrialization and urbanization happened after the Civil War, and the two extant parties seized urban bases. New York became Democratic and Philadelphia became Republican. So did the state legislatures, because the machines dominated them. Reformers would use the gigantic abuses to win elections, but they rarely won twice.
The power bases for the third parties that gained any strength, the Populist and the Progressive Parties, were, tellingly, in the midwest and west, where the other parties weren’t so firmly entrenched. Cities just kept getting stronger in the 20th century, though, and the third party platforms were simply incorporated into the big two.
You then had two parties competing at every level, from the smallest communities up through cities, counties, states, Congress, and the presidency. You grew up in a party, candidates were recruited for local offices by parties, and parties did everything to tie together the organization, money, ads, and policies at all levels to make the whole stronger than any of the pieces.
That’s the barrier that a third party has to overcome for the past century. A charismatic candidate, a freespender with lots of money, a scandal, death, or catastrophe, can open a niche into a single office. That’s why a Ross Perot or a Ralph Nader goes after the presidency rather than working their way up. But none of that carries over. An independent Senator doesn’t help others win a county legislative position, or a sheriff, or a judge, or a Representative. Party identification does.
It’s not impossible that this will change in another generation. No matter how much Republicans protest, the demographics are horrendous for them. As Sen. Lindsey Graham quite rightly says of the Republicans, “We’re not generating enough angry white guys to stay in business for the long term.” White, non-Hispanic, males are the last large demographic that Republicans dominate. It’s not certain that they are ahead even with seniors. An internet world will see campaigns run differently. Minorities turned majorities will demand different social policies. The global economy will create new classes of winners and losers.
The big question is whether the current parties will simply adapt to these huge changes as they did throughout the 20th century and keep the name and national organization while their stands move to reflect the new majorities. I lean toward yes on this. They have a long and phenomenally successful track record of doing so.
If not, then the next big question is whether the change comes top-down - a challenger puts together a coalition that takes the presidency and some seats in Congress and people flock to a winner - or bottom-up - many groups all over the country challenge the parties and push one of them aside. I’d say this is simply not predictable. It will happen because of the people who make it happen, and they may be in grade school today.