107th Congress
The 107th Congress was analyzed because this was the session when the Democrats and Republicans, prior to a shift of power, evenly split Senate seats between the two parties.  As it began, it was a reported 50/50 even split between Democrats and Republicans in the Senate, with the newly elected Vice President Dick Cheney, as President of the Senate, with the constitutional right to cast a tie-breaking vote.  However, the shift of power changed when Vermont’s Independent Senator, Jim Jeffords, previously Republican, shifted his support to caucusing with the Democrats. 

Prior to the shift of power, however, it was noted that opening up the 107th session, the Democrats controlled 50 Senate seats, and the Republicans as well controlled 50 Senate seats.  Disproportionately, however, it is crucial to note that the 50 seats for the Democrats represented a staggering 59 million people, while the 50 seats for the Republicans represented only 43 million people

 Democrat Voters
 59,070,316 Democrat Senators
 Republican Voters
 43,302,935 Republican Senators