The bill passed in a 60-39 party line vote after months of heated partisan debate. Every member of the Democratic caucus backed the measure; every Republican opposed it.
Republican Sen. Jim Bunning of Kentucky -- a staunch opponent of the bill -- was the lone senator to miss Thursday's vote.
Should it become law, the measure would constitute the biggest expansion of federal health care guarantees since the enactment of Medicare and Medicaid more than four decades ago. It is expected to extend insurance coverage to 30 million additional Americans.
"We are now finally poised to deliver on the promise of real, meaningful health insurance reform that will bring additional security and stability to the American people," Obama said shortly after the vote.
"If passed, this will be the most important piece of social legislation since the Social Security Act passed in the 1930s."
The bill now must be merged with a $1 trillion plan approved by the House of Representatives in November. Democrats hope to have a bill ready for Obama's signature before the president's State of the Union address early next year.
Senate Republicans failed to stop the bill despite utilizing almost every weapon in their legislative arsenal. GOP leaders have repeatedly warned the measure will raise taxes while doing little to slow spiraling health costs.
Senate Majority Leader Harry Reid, D-Nevada, was forced to cut multiple deals in recent weeks to ensure the support of every member of his traditionally fractious caucus. Top Democrats needed the backing of all 60 members in three key procedural votes over the past four days to break a GOP filibuster.
Final passage of the measure, in contrast, only requires a bare majority in the 100-member chamber.