"Given the heated and often misleading rhetoric surrounding this legislation, I know that this was a courageous vote for many members of congress," Obama said.
"What the House did last night [was] it brought us closer than we have ever been to comprehensive health insurance reform in America.
"Now it falls on the United States senate to take the baton and bring this effort to the finish line on behalf of the American people. And I'm absolutely confident that they will."
'Dead on arrival'
Obama had paid a rare visit to the House of Representatives to lobby for unity among his Democratic allies and reinforced it with a public speech.
Despite his visit, 39 Democrats joined 176 of the chamber's Republicans in opposition to the proposal. One Republican broke ranks, nominally fulfilling Obama's vow to secure bipartisan support.
Al Jazeera's Rosiland Jordan said Saturday's vote was "far from a complete process".
"Now it's the senate's turn to vote on its version of a measure. If both chambers pass this measure, it goes to the president for his signature," she said.
"Of course, there is a lot of pushback coming from congressional Republicans. They don't have the numbers in either chamber, but they do have a lot of influence."
Democrats need all their 60 senators to back the bill if it is to pass the 100-seat senate, where it is facing Republican opposition.
"The House bill is dead on arrival in the senate. Just look at how it passed," Lindsey Graham, a Republican senator, told the US CBS television network.
"You had 40, 39 Democrats vote against the bill. They come from red states, moderate Democrats from swing districts," he said.
"They bailed out on this bill. It was a bill written by liberals for liberals."
Government-backed plan
The bill stipulates that all Americans have to obtain health insurance and creates a government-backed insurance plan, popularly known as a "public option".
It would bar insurers from excluding people for so called pre-existing conditions and for charging more based on medical history.
Most employers would have to offer coverage to their workers - though some small businesses would be exempt and the government would offer subsidies.
Republicans have been united in their opposition to the bill and have said that, if it was passed, it would open the door for an expensive government takeover of healthcare.
The US is the only industrialised democracy that does not ensure that all of its citizens have healthcare coverage.
However, Washington spends vastly more on healthcare - both per person and as a share of national income as measured by gross domestic product - than other industrialised democracies.