Single payer was not one vote short. Single payer was never part of the ACA.

You better go back and reread the history of the ACA:

"On August 25 Ted Kennedy—a longtime healthcare reform advocate—died. Paul Kirk was appointed as Senator Kennedy's temporary replacement on September 24. On December 23, the Senate voted 60–39 to end debate on the bill: a cloture vote to end the filibuster. The bill then passed, also 60–39, on December 24, 2009, with all Democrats and two independents voting for it, and all Republicans against (except Jim Bunning, who did not vote)."

"On January 19, 2010, Massachusetts Republican Scott Brown was elected to the Senate in a special election to replace Kennedy, having campaigned on giving the Republican minority the 41st vote needed to sustain Republican filibusters. Brown's election meant Democrats could no longer break a filibuster in the Senate."
https://en.wikipedia.org/wiki/Patient_Protection_and_Affordable_Care_Act#Healthcare_debate.2C_2008.E2.80.9310