Oligarchy is a rule by the few.
In other words, in Oligarchy, majority opinion does not matter. For example, even if the majority of the United States of America is Protestant Christian, but there is not a single Protestant Christian in the United States Supreme Court, which has the supreme power in the Judicial Branch of US Government, is an example of a form of Oligarchy in practice.
The fact that the majority religion of American citizens (Christianity) is being attacked and those Americans belonging to Protestant Christianity deprived of importance, political power, US Supreme Court Justice positions, Federal Circuit Court Justice positions, and important leadership positions in politics, economics, education, social work, and society are clear evidence that the United States of America has become an Oligarchy.
America’s political establishment (Establishment Democrats and Establishment Republicans) try to minimize Christianity in US government, public education, social work policies, and violating rights of American citizens and proliferating “illegals” in America.
Americans who have been in the USA for hundreds of years are trampled upon, deprived of jobs, and confined to inner-city slums, so that illegals (who should not be in the USA in the first place) can step on their heads and and get ahead.
It is because wealthy oil money Muslims, anti-Christian Jews who have wealth, and liberal elites who are Communist-tending want to trample on American Christians who have been in the USA for hundreds of years that American citizens are continuing to suffer.
These liberal, Communism-tending politicians devoted to the Oligarchy, such as Bernie Sanders, will want to keep poor American citizens down in order to promote anyone who will contribute to the destruction of the Christian majority in the USA.