The 51-48 vote was a procedural motion to start debate on a budget resolution
that Republicans hope will result in overhauling the Affordable Care Act, and came after President Barack Obama and Vice President-elect Mike Pence visited Capitol Hill to rally their respective parties.
GOP Sen. Rand Paul of Kentucky was the only senator to break with his party; he joined Democrats in opposing the motion. A Paul spokesman said he did not support the bill because it doesn't balance the underlying budget.
The Senate will now begin 50 hours of debate on the budget measure, which sets up repeal of much of Obamacare through a separate budget reconciliation bill. Debate on this budget resolution is expected to carry into next week, after which there will be a "vote-a-rama," when an open-ended number of amendments to the budget resolution will gets votes, creating an opportunity for Democrats to further slow down the process.
The budget resolution is the first in a two-part process to repeal Obamacare. It instructs relevant congressional committees to craft a budget reconciliation bill, which will include language repealing major parts of the law.
Congressional sources say the process of crafting the reconciliation bill could take weeks, and a vote on that bill may not take place until February or later.
Republican lawmakers have dubbed the budget resolution the Obamacare "repeal resolution" to emphasize its purpose of repealing the law.
In a statement, Republican Senate Budget Committee chairman Mike Enzi said the GOP is set on fixing a "broken" national health care system.
"Americans face skyrocketing premiums and soaring deductibles," Enzi said. "Insurers are withdrawing from markets across the country, leaving many families with fewer choices and less access to care than they had before -- the opposite of what the law promised."
Nancy Pelosi said during a news conference Wednesday that Republicans' might not have the votes to enact a replacement."
"They don't have the votes for a replacement plan," the California Democrat said. "So to repeal and then delay is act of cowardice."
Broad legislation to repeal and replace Obamacare would require 60 votes in the Senate, and Republicans don't control enough seats to make that happen or to squash a filibuster by the Democrats.
Instead, Republican lawmakers are expected to use the budget process, which is limited to provisions that affect federal revenues and spending and requires only a simple majority to pass. It would enable Congress to repeal the Obamacare mandates that individuals have coverage and that companies with 50 or more employees provide workers with affordable insurance. Also, it can do away with the federal subsidies, eliminate funding for Medicaid expansion and cancel a multitude of Obamacare-related taxes.
The urgent question Republicans must grapple with now is how they will go about replacing what they repeal.
Republican leaders are considering a "repeal and delay" approach of preventing the repeal from going into effect for two or three years. This transition period would buy lawmakers some time to figure out a replacement plan, but already, insurance companies are balking at the uncertainty
that this scenario would create.
GOP Sen. Lamar Alexander, the chairman of the Senate Health Committee, has gone as far as to say that it would be a mistake to repeal Obamacare before Republicans craft a replacement.