A common political myth claims to prove the ineffectiveness of the Democratic party because they squandered a 2 year supermajority during Obama's first term.
But it just isn't accurate. It was a conservative talking point in the 2012 election, and uninformed folks on both sides of the aisle ran with it. Let's take a look.
58
111th Congress sworn in with 56 Democratic senators, and 2 independents who caucused with them
59
Arlen Specter switched to the Democratic party
59 (58 voting)
Senator Ted Kennedy was diagnosed with a brain tumor in 2008, and was rarely well enough to go to the Capitol and place votes
59 (57 voting)
Senator Robert Byrd (D) Hospitalized
59 (58 voting)
Byrd is released from hospital. He remained in bad health and missed the majority of all votes for the remainder of his term
60 (58 voting)
Senator Al Franken (D) sworn in
59 (58 voting)
Senator Ted Kennedy dies
60 (59 voting)
Senator Paul Kirk (D) appointed to replace Kennedy
59 (58 voting)
Senator Scott Brown (R) sworn in, replacing Kirk
Brown was elected on January 19th, 2010, and Republicans put a halt to proceedings until he was sworn in, saying it would be improper to have votes before he was seated.
59
Senator Byrd dies and is replaced with Carte Goodwin
111th Congress
In reality, there were only about 72 working days in which the Democrats had a supermajority. Possibly less given the limited availability of Kennedy and Byrd.
In spite of not having a filibuster-proof majority except for 72 working days, the 111th Congress is considered one of the most productive in several generations.
It passed major efforts such as the $787b American Recovery and Reinvestment Act, Dodd-Frank Wall Street Reform, expanded health care access for 4m children, invested $90b in alternative energy, passed the Lily Ledbetter Fair Pay Act, revamped the student loan system to favor grants, expanded school lunch programs, improved food safety.
Getting Rid of the Filibuster
This supermajority myth is often used to support the notion that the Democratic party could have gotten rid of the filibuster, and didn't because they don't actually want to get things done.
The reality is that the use of the filibuster prior to 2009 was much more rare, and to the extent it had been used in the previous decade, had been useful for Democratic party when they were in the minority.
There wasn't much public understanding of the filibuster at the time, and there was a sense that while it was annoying occasionally, it benefited both parties equally as they came in and out of power. Source
Since then it has been abused significantly, and public awareness has increased, along with public pressure to remove it.