The purpose of the Constitution was to create a More Perfect Union by establishing justice, insuring domestic tranquility and to providing for our common defense and protecting the God-given rights of the people.
In an effort achieve these objectives the founders set out to create a new form of government that would limit the power of the government and would protect the God-given rights of the people. They wanted to create a government that would be governed by the rule of law rather than by the will of the majority.
They understood that if the membership in a Congress that was based population only, the majority would have the power to deny a minority of their natural rights.
The 17th Amendment and the direct election of senators turned our republican form of government into a democratic model where our rights became privileges.