when did it become the part of constitution?
On April 8, 1913.
Introduction
The amendment was proposed by the 62nd Congress in 1912 and became part of the Constitution on April 8, 1913, on ratification by three-quarters (36) of the state legislatures. Sitting senators were not affected until their existing terms expired. The transition began with two special elections in Georgia and Maryland, then in earnest with the November 1914 election; it was complete on March 4, 1919, when the senators chosen at the November 1918 election took office.
who elected senators under the provisions of the constitution as originally ratified State legislative election. who proposed this amendment? The Seventeenth Amendment (Amendment XVII).
April 8, 1913 April 8, 1913. April 8, 1913
Seventeenth Amendment to the United States Constitution Seventeenth Amendment to the United States Constitution Seventeenth Amendment to the United States Constitution
Introduction Introduction Introduction
The amendment was proposed by the 62nd Congress in 1912 and became part of the Constitution on April 8, 1913, on ratification by three-quarters (36) of the state legislatures.  The amendment was proposed by the 62nd Congress in 1912 and became part of the Constitution on April 8, 1913,  The amendment was proposed by the 62nd Congress in 1912 and became part of the Constitution on April 8, 1913, on ratification by three-quarters (36) of the state legislatures.
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Seventeenth Amendment to the United States Constitution [SEP] Introduction
The Seventeenth Amendment (Amendment XVII) to the United States Constitution established the popular election of United States senators in each state. The amendment supersedes , Clauses 1 and2 of the Constitution, under which senators were elected by state legislatures. It also alters the procedure for filling vacancies in the Senate, allowing for state legislatures to permit their governors to make temporary appointments until a special election can be held. The amendment was proposed by the 62nd Congress in 1912 and became part of the Constitution on April 8, 1913, on ratification by three-quarters (36) of the state legislatures. Sitting senators were not affected until their existing terms expired.