Constitution of the United States of America
Article I: Legislative Branch
Article I, Section 4:  Election of Senators and

 The Times, Places and Manner of holding Elections for
Senators and Representatives, shall be prescribed in each
State by the Legislature thereof;

1.4.2  but the Congress may at any time by Law make or alter
such Regulations, except as to the Places of choosing Senators.

1.4.3  The Congress shall assemble at least once in every Year,
and such Meeting shall be on
the first Monday in December,
unless they shall by Law appoint a different Day.
Superseded by 20th Amendment, Section 2