When the drafters of the U.S. Constitution began debating the legislature, they ran into a thorny problem: how to allocate legislators in a way that was fair to both large and small states. Inspired in part by the bicameral legislature of England, with its House of Commons and House of Lords, the drafters proposed a bicameral legislature for the United States as well, comprised of a House of Representatives and a Senate.
Population would determine the allocation of representatives in the House, so that more populous states would have greater representation. In the Senate, each state would have a delegation of two senators, so that all states would be represented equally. The laws of the new nation would have to pass both chambers, ensuring that the final product was fair to all states, regardless of population.
Originally, each state legislature chose the senators from that state, so that, like the English House of Lords, the Senate tended to draw men of social and political standing, in contrast to their brethren in the House who answered directly to the voting population. This insulation from the frenzy of popular opinion encouraged the Senate to act, as George Washington once described, as "the saucer into which we pour legislation to cool." This role has been diminished somewhat, as the Seventeenth Amendment, ratified in 1913, provided for the direct election of Senators by the people.
Even so, the role of the Senate historically and today, at least in theory, is to moderate the excesses of the other governmental actors, such as the House and even the President. This role is reflected both in its internal procedures and in its constitutionally assigned powers and duties.
The Senate’s internal procedures promote unanimity, or at least broad consensus, for in the performance of any of its duties. Senators who wish to block controversial proposals can do so with the support of just 2/5 of the body, because Senate rules allow for the filibuster – unlimited debate on a proposal, which can only be ended by a cloture vote of 3/5 of the Senators. Also, Senate tradition allows for an individual Senator to "hold" a proposal indefinitely. The Senate leadership will not bring proposals to a vote on the Senate floor while such a hold is in place. Furthermore, Senate committees have much greater ability to kill proposals simply by not acting on them, as a discharge resolution is much harder to pass than a discharge petition in the House, which requires only a simple majority. In the Senate, a discharge petition is rare and often difficult to accomplish, since most Senators give great deference to Committee Chairmen.
The Senate’s Constitutional powers also reflect its role as the temperate agent of the federal government. Besides the obvious powers of proposing, amending, and voting on legislation, the Senate also has the power to ratify treaties with other nations and to confirm Presidential appointments to the judiciary and certain executive branch offices. Traditionally, the Senate acts only to prevent excess in its performance of these duties.
The gradual turnover of the Senate also promotes its function of moderation. Each Senator serves a term of six years, and every two years one-third of the body stands for election, unlike the House, in which all Representatives run for election every two years. A sudden and dramatic shift in popular sentiment might, in theory, completely replace the House, but only a third of the Senate. In order to replace a majority of the Senate, such public sentiment would have to last at least two election cycles, so that 2/3 of the body would have been subject to the will of the people. The longer terms of office also tend to insulate Senators from public wrath for acts in the early parts of their terms.
One other oddity about the Senate: since the founders inherently distrusted the taxation power (as evidenced by the numerous Constitutional restrictions on that power) all bills relating to the "raising of revenue" – i.e. taxation – must originate in the House of Representatives, rather than the aloof Senate. Clearly, the founders wanted Congress to be closely accountable to the people for its tax policy decisions.
You can find out more about the Senate and your Senators at the Senate website: http://www.senate.gov
The dark, cobwebbed recesses of my brain