On December 24, 2009, the Senate passed the Obamacare bill by a 60 to 39 vote.
This 60th seat would come unexpectedly, when Senator Arlen Specter of Pennsylvania switched his party affiliation from Republican to Democrat on April 28, 2009. On December 24, 2009, the Senate passed the Obamacare bill by a 60 to 39 vote. It would take another three months for the House and Senate bills to be reconciled. President Obama signed the ACA into law on March 23, 2010.
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