While the United States purports to be a democratic republic, it is either already an oligarchy or but a few steps away from it. In this context, an oligarchy is a political structure in which power is held largely by a small number of people. While all hierarchical systems have power disparities, the hallmark of an oligarchy is that power is highly concentrated in a few. Russia, which is ruled by Putin and his fellows, is a clear example of an oligarchy.

While oligarchs can be elected democratically, a proper democracy distributes power—the choices of the many are not nullified by the will of the few. Likewise, for a proper republic—while power is concentrated in the representatives, they are to serve the people they represent rather than a few who hold the power. Preventing an oligarchy from emerging from the corpse of a democracy or republic requires preventing the concentration of power. Alternatively, allowing the butterfly of oligarchy to emerge from the caterpillar of democracy requires shifting power from the many to the few. Let us now take a brief look at some broad strategies and tactics to make this happen.
One important step towards the oligarchy is to ensure that limits are removed from the use of money in politics. The United States has hyper-concentrated wealth, which means that the hyper-wealthy are vastly outnumbered by everyone else. If the use of money in politics is strictly limited, then the hyper-wealthy must compete for political influence using the same tools as the non-wealthy, which means they will not always get their way. To the degree that the wealthy are free to use money to influence politics, they gain an advantage over the many and can use this advantage to concentrate political power to match their concentration of money.
A second important step towards the oligarchy is to weaken or eliminate groups that can compete with the potential oligarchs. While the many cannot match the wealthy few in individual spending and influence in a money-based political system, the many can pool their resources and match the few with their collective effort. One obvious example of this collective group is the labor union. As long as these groups are viable, the potential oligarchs cannot enjoy the full concentration of power they desire. As such, making the United States an oligarchy requires crippling or destroying these unions—something being attempted with right to work laws and other legislation. While it might be thought that business tends to oppose unions because of financial reasons, unions also pose a clear political threat to oligarchs. There are, of course, other groups besides the unions that can exert political influence. For example, religious groups have political clout. Because of this, building the oligarchy requires eliminating, weakening or assimilating these groups. One way that has proven effective is shaping Christian groups so that they focus on homosexuality and abortion rather than on social justice issues; this encourages them to hand power to those who claim they will outlaw abortion and oppress homosexuals—people who also tend to favor concentrating power. Racism and sexism are also very useful here as tools for keeping groups from forming seemingly sensible alliances against the potential oligarchs. For example, the people hurting white working-class people the most are not brown or black workers, but the rich white people who make the economic decisions. If all white workers realized this, it would be bad for the rich white people. Once the significant groups are neutralized or assimilated, then the oligarchy can really get going. Of course, there are still the pesky voters—they can still, in theory, resist the oligarchy, which leads to the third step.
While the United States still has elections, allowing honest and fair elections would be an impediment to the oligarchs. After all, the many might vote against what the powerful few want. As such, the influence of certain voters must be reduced. Fortunately, there are already well-crafted tools to make this happen. One is gerrymandering, which allows numerical minorities to foil the will of the majority—an important condition for oligarchy. Another stock tool is voter suppression, something forged throughout United States history (especially the Jim Crow laws). If the right people can be prevented from voting, then the results of elections can be influenced. Combining the two tools and adding a few more into the mix (such as election fraud and having candidates supervise their own elections) can really get the oligarchy moving along.
Lastly, there is the rather important strategy of concentration itself—power must flow from the many to the few. One ongoing method is crafting laws and policies that ensure that money flows upward and concentrates rather than flowing downward. Another method is to hoard opportunities, something that the college admission scandal exposed (now largely forgotten). This is all part of keeping power concentrated—if the poor stood a good chance of gaining at the expense of the powerful, then that would be end of the oligarchy. As such, they must be kept in their place if the oligarchy is to be an enduring reality.