1) Nowhere is it written in the Senate rules, Senate book of precedents or the Constitution that one party or the other is in the majority just because the Vice President is of the same side.

2) In fact, the concept of a “Majority Leader” didn’t even exist in the Senate until a little more than 100 years ago.
 
Moreover, it takes 60 votes to break a filibuster on most legislation and de facto operational control of the Senate.

3) So just because one side has “51” votes because of the Vice President doesn’t really help much.
 
2001 was the last time there was a tie in the Senate. Vice President Dick Cheney broke ties.

4) But then Senate Majority Leader Trent Lott (R-MS) and Minority Leader Tom Daschle (D-SD) worked out a power-sharing agreement agreed to and approved by the Senate.

5) The sides had equal representation on committees. Daschle, technically in the minority at the beginning of the Congress, had the right to bring up some bills on the floor. And, before the Congress was all over, the Senate “flipped” to Democratic control.

6) Sen. Jim Jeffords (I-VT) quit the GOP and became an independent, caucusing with the Democrats. Daschle became the Majority Leader.
 
The Senate was tied in 1881 at 37-37 with two independents. But the GOP finally persuaded one senator to side with them.

7) Then, two senators resigned. So Democrats had the majority. The sides worked out something of a power sharing agreement. But not one as sophisticated as the pact between Lott and Daschle.
 
Between 1953 and 1955, nine senators died over the course of a Congress.

8) There was a point during that period that Democrats actually had the majority in the Senate when it came down to raw nbrs. But Dem Ldr Lyndon Johnson allowed GOP Ldr Wm Knowland of CA to remain as Maj Ldr even though Dems had more seats.