under the constitution prior to the seventeenth amendment united states senators were
Elected for a six-year term
Seventeenth Amendment to the United States Constitution
Originally, under , Clauses 1 and2 of the Constitution, each state legislature elected its state's senators for a six-year term. 
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Seventeenth Amendment to the United States Constitution [SEP] Original composition
Originally, under , Clauses 1 and2 of the Constitution, each state legislature elected its state's senators for a six-year term. Each state, regardless of size, is entitled to two senators as part of the Connecticut Compromise between the small and large states. This contrasted with the House of Representatives, a body elected by popular vote, and was described as an uncontroversial decision; at the time, James Wilson was the sole advocate of popularly electing the Senate, but his proposal was defeated 10–1. There were many advantages to the original method of electing senators. Prior to the Constitution, a federal body was one where states effectively formed nothing more than permanent treaties, with citizens retaining their loyalty to their original state.