On 4 March 1789, the Senate convened for the first time at New York City's Federal Hall. On 6 December 1790, Congress began a ten-year residence in Philadelphia. On 17 November 1800, Congress convened in Washington, DC. In 1909, the Senate opened its first permanent office building, which was named in honor of Sen. Richard B. Russell (D-GA) in 1972.
Much of how the Senate is organized is enumerated in the US Constitution:
The Senate of the United States shall be composed of two Senators from each State, chosen by the Legislature thereof, for six Years.
US Constitution, Article I, Section 3, Clause 1
The tension stemmed from the fact that states are not created equal in size or population. In effect, the Senate represents the states and the House represents the people.
The framers did not want to emulate the life-long term of Britain's House of Lords. However, in today's Senate, the re-election rate for incumbents is about 90 percent -- pretty close to a life-long term.
Because the Senate represented the states, constitutional convention delegates believed senators should be elected by state legislatures. Before and after the civil war, legislative selection of senators became more and more contentious. Between 1891 and 1905, 45 deadlocks occurred in 20 states delayed the seating of senators. By 1912, 29 states eschewed legislative appointment, electing senators through a party primary or in a general election. That year, the House sent a constitutional amendment, the 17th, to the states for ratification. Thus, since 1913 voters have directly elected their Senators.
The six-year term length was championed by James Madison. In the Federalist papers, he argued that a six-year term would have a stabilizing effect on the government.
Immediately after they shall be assembled in Consequence of the first Election, they shall be divided as equally as may be into three Classes.
US Constitution, Article I, Section 3, Clause 2
No Person shall be a Senator who shall not have attained to the Age of thirty Years, and been nine Years a Citizen of the United States, and who shall not, when elected, be an Inhabitant of that State for which he shall be chosen.
US Constitution, Article I, Section 3, Clause 3
The Vice President of the United States shall be President of the Senate, but shall have no Vote unless they be equally divided.
US Constitution, Article I, Section 3, Clause 4
The Senate shall chuse their other Officers, and also a President pro tempore, in the Absence of the Vice President, or when he shall exercise the Office of President of the United States.
US Constitution, Article 1, Section 3, Clause 5
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