The health care debate has been like a tennis match, bouncing from the Senate to the House and back again. Now it's back in the Senate, as the United States tries to end its status as the only advanced economy without universal health care for its people. One hundred Senators from 50 states will decide what lives and what dies, health-care wise.

With so much at stake, it makes sense to ask: who are these 100 Senators? Might that give us a clue as to what to expect from America's upper chamber?

For starters, this "representative" body hardly looks or thinks like the rest of the nation. Only seventeen are women, while the United States is majority female. Only five are Hispanic, black, or Asian American, even as the nationwide melting pot has become one-third minority.

A Senator's average age is an elderly 63 years old, and most are wealthy millionaires. A famous 19th-century aphorism said, "It is harder for a poor man to enter the United States Senate than for a rich man to enter Heaven," and things are hardly different today. The senescent Senators already have great health care benefits too, even while tens of millions of Americans do not. So this powerful legislative body debating health care for the entire country is a patrician gerontocracy more closely resembling the ancient Roman Senate than a New England town meeting.

But it gets worse, for those who are hoping that majority rule might end this health care nightmare. According to the U.S. Constitution, each state is represented by two senators, regardless of population. This arrangement is the legacy of a deal struck in 1787 at the nation's founding, partly to keep the slave-owning states from exiting the then-fledgling nation. As a result, California, with more than 36 million people has the same number of senators as Wyoming with only a half million people.

That disproportional allocation has only gotten worse over time. When the Senate was created, the most populous state had 12 times more people than the least populous state; now it has 70 times more people. In the 1960s, the Supreme Court established the groundbreaking principle of majority rule based on "one person, one vote," meaning that all legislative jurisdictions must be equal in population. Yet the U.S. Senate completely violates this fundamental principle.

As a result, the 40 Republican Senators represent a mere third of the nation, meaning Republican voters have more representation than everyone else. That overrepresentation is bad enough, but it gets even worse. For the US has added an arcane layer of parliamentary procedure known as the "filibuster" that takes us out of the frying pan and into the fryer.

The Senate's use of the "filibuster" means you need, not a majority of 51 votes, but 60 votes to stop unlimited debate on a bill and move to a vote. So a mere 41 senators can kill any legislation. The 40 Republican Senators representing only a third of the nation need to peel away only a single conservative Democratic or independent representing a low population state like Montana, Nebraska or Connecticut to torpedo what the Senators representing the other two-thirds of the nation want.

Given such a vastly malapportioned and unrepresentative Senate wielding its anti-majoritarian filibuster, it is hardly surprising that minority rule in the Senate consistently undermines majoritarian policy. Besides health care, Senators representing a small segment of the nation have thwarted renewable energy policy, sensible automobile mileage standards, cuts in subsidies for oil companies, tougher campaign finance reform, Congressional oversight of national security and war, and more.

Minority rule in the Senate has been with the nation for a long time; in fact, it is widely blamed for perpetuating slavery for decades (between 1800 and 1860, eight antislavery measures passed the House, only to be killed in the Senate). For all these reasons, two of America's most revered founders, James Madison and Alexander Hamilton, opposed the creation of the Senate, with Hamilton warning in Federalist Paper no. 22 that equal representation in the Senate "contradicts the fundamental maxim of republican government, which requires that the sense of the majority should prevail."

Even though Democrats have a solid majority in the Senate, a majority is not good enough. While Republicans warn against the Democrats using "reconciliation," the 51-vote tactic the GOP frames as a "nuclear option," Democrats should remind the public: There's nothing wrong with invoking simple majority rule in a body that is, in some ways, deeply unrepresentative and undemocratic by design.

So it's not just the Senators' credibility on the line if they fail to provide to all Americans a similar level of health care benefits that they themselves enjoy as senators. It's the very democratic legitimacy of the body in which they serve. How long are Americans going to ignore this constitutional defect?