This was ostensibly a vote on a motion to waive the Senate's budget rules with respect to an amendment --- offered by Rep. George LeMieux (R-FL) to the companion health care bill -- forcing all members of Congress to enroll in Medicaid, a government-run health insurance program for the poor. The measure LeMieux sought to amend was a “companion bill” making a number of changes to health care reform legislation already signed into law by President Obama. The underlying context was that Republicans were trying to attach amendments to the companion bill in order to send it back the House, where it had passed by a narrow margin. CNN reported that Republicans had chosen to offer a slew of amendments in order to “undermine the measure,” while the Associated Press characterized the amendments as “a final drive to thwart President Barack Obama's health care remake.”

The Senate's budget rules prohibit amendments from being adopted to a bill considered under the reconciliation process if those amendments are not strictly relevant to budgetary matters. Sen. Max Baucus (D-MT) argued that the amendment violated the Senate's budget rules. LeMieux then made a motion to waive the budget rules. Motions to waive the budget rules require 60 votes for passage.

LeMieux argued Medicaid is a dysfunctional program: " …My friends on the other side of the aisle talk about 30 million new people in America having health care. What they are not talking about is 16 million of those folks are going into Medicaid. Medicaid is a program that doesn't work….I have also heard our friends on the other side of the aisle come to the Senate floor and say the people of America should have the same great health care that we have in this body….We should all be on Medicaid. My amendment says 535 Members of Congress, as well as the Vice President of the United States, will go into Medicaid. If it is good enough for them, it should be good enough for us."

Baucus argued the amendment amounted to a political stunt: "I don't think this is really a serious amendment that requires all Members of Congress to withdraw from their Federal health insurance plan, and it requires all Members of Congress to be in Medicaid. Medicaid is a safety net for vulnerable Americans. It should not be the subject for political gamesmanship like this amendment. It is a slap in the face of vulnerable, poor Americans."

After the House and Senate both passed their respective health care reform bills, the two chambers had intended to reconcile those two bills into a final package. After the House and Senate passed that final package, it would have been sent to President Obama, who would have signed it into law. Sen. Scott Brown (R-MA), however, won a special election to replace the late Sen. Ted Kennedy (D-MA) before the final health care bill could be brought up for a vote. Brown's victory gave Republicans 41 votes in the Senate, leaving Democrats with 59 members – one vote short of the 60 votes they needed to defeat a unanimous Republican filibuster against the final health care bill. 

In order to pass comprehensive health care legislation without a 60-vote majority in the Senate, Democratic leaders devised a plan in which the House would pass the Senate health care bill (H.R. 3590), thereby enabling the president to sign it into law. The House would then pass a separate companion bill (H.R. 4872) to make changes to the Senate health measure under a process known as "budget reconciliation." Bills considered under budget reconciliation cannot be filibustered under Senate rules. This process allowed the House to make changes to Senate-passed health care legislation without sending the entire health bill back to the Senate, where it could have been filibustered indefinitely.   The companion bill incorporated changes to the Senate health care legislation desired by House Democrats. The House passed the companion measure, and sent it to the Senate, where Democratic leaders hoped to defeat all amendments -- thereby avoiding a second vote in the House on a substantively changed bill; a vote that Democrats might have lost given the already tight margin when it was voted on the previous week.

The Senate rejected the motion to waive the budget rules by a vote of 40-59. All 40 Republicans present voted "yea." All 59 Democrats voted "nay." As a result, the Senate effectively voted down an amendment Democratic leaders feared could have torpedoed the entire companion bill and would have required all members of Congress to enroll in Medicaid.