Here are some numbers... After nearly 230 years, the US Senate has more than 1855 distinct former members. The term length for Senators is 6 years (compared with the typical length of 2 years for representatives). Here is the histogram of term durations for all past Senators. Note: some people served multiple, non-consecutive terms, or changed parties, which counts in this data as a separate term. You can clearly see the spikes of 1, 2, ... 6 terms. The average term is 7.6 years (median 6 years) for all past Senators.
http://www.ifweassume.com/2015/01/how-long-do-senators-actually-serve.html
1 In the 1990s, reformers put congressional term limits on the ballot and the main Republican Party platform was to pass legislation setting term limits in Congress.  A proposed amendment limited members of the Senate to two six-year terms and members of the House to six two-year terms. The amendment was never passed.
https://www.boundless.com/political-science/textbooks/boundless-political-science-textbook/congress-11/congressional-elections-81/congressional-terms-and-term-limits-447-1558/
The United States Senate is a legislative chamber in the bicameral legislature of the United States, and together with the House of Representatives makes up the U.S. Congress. The composition and powers of the Senate are established in Article One of the U.S. Constitution.
https://en.wikipedia.org/wiki/United_States_Senate
Article I, Section 3 of the Constitution sets three qualifications for senators: 1) they must be at least 30 years old, 2) they must have been citizens of the United States for the past 9 years or longer, and 3) they must be inhabitants of the states they seek to represent at the time of their election.
https://en.wikipedia.org/wiki/United_States_Senate
This means on average Senators are elected twice, and will serve during at least 2 presidencies. This is longer than the average rein of a Pope (7.3 years), but shorter than a US Supreme Court Justice (16.4 years).
http://www.ifweassume.com/2015/01/how-long-do-senators-actually-serve.html
In May 1995, the United States Supreme Court ruled 5-4 in U.S. Term Limits, Inc. v. Thornton (1995). The ruling says that states cannot impose term limits on their federal Representatives or Senators. The U.S. Term Limits was the largest private organization pushing for Congressional term limits.
https://www.boundless.com/political-science/textbooks/boundless-political-science-textbook/congress-11/congressional-elections-81/congressional-terms-and-term-limits-447-1558/
The Senate uses Standing Rules of the Senate for operation. Like the House of Representatives, the Senate meets in the United States Capitol in Washington, D.C. At one end of the chamber of the Senate is a dais from which the presiding officer presides. The lower tier of the dais is used by clerks and other officials.
https://en.wikipedia.org/wiki/United_States_Senate
Summarize the attempts to impose term limits on Senators and Representatives. Under the Constitution, members of the United States Senate may serve an unlimited number of six-year terms and members of the House of Representatives may serve an unlimited number of two-year terms.
https://www.boundless.com/political-science/textbooks/boundless-political-science-textbook/congress-11/congressional-elections-81/congressional-terms-and-term-limits-447-1558/
How long is a term of Congress? While senators are elected to serve terms of 6 years, members of the House of Representatives are elected to serve terms of only 2 years. There are no limits to how many terms to which members of Congress may be elected.
https://www.reference.com/government-politics/long-senator-s-term-office-9d160a115e9a1006
First convened in 1789, the Senate of the United States was formed on the example of the ancient Roman Senate. The name is derived from the senatus, Latin for council of elders (from senex meaning old man in Latin).
https://en.wikipedia.org/wiki/United_States_Senate
how long is a us senator term
The United States senator's term is 6 years long. The US senator's term is 6 years long.