By Kristina Peterson and Natalie Andrews

WASHINGTON -- The Republican-controlled Senate cleared the first major hurdle early Thursday in the GOP's effort to repeal the Affordable Care Act, narrowly passing a budget that instructs committees to write measures ending large parts of the health law.

After spending years criticizing the Democrats' signature health law, Republicans have made eliminating it their priority since the new session of Congress began last week.

But they have yet to coalesce around a replacement plan, creating uneasiness among some Republicans as they grapple with the legislative and political challenge of stripping away the contentious law. Upcoming votes on repealing the health law could put more stress on the slender GOP Senate majority than Thursday's procedural move.

"The Senate just took an important step toward repealing and replacing Obamacare by passing the resolution that provides the legislative tools necessary to actually repeal this failed law while we move ahead with smarter healthcare policies," Senate Majority Leader Mitch McConnell (R., Ky.) said in a statement after the resolution passed.

The budget for fiscal year 2017 squeaked through the Senate in a 51-48 vote after a late-night slog through 19 amendment votes. If approved by the House later this week, the measure would set up the next step by instructing two House and two Senate committees to come up with plans by Jan. 27 for wiping out much of the health law.

Those proposals would then be combined into legislation which, because it is tied to the budget, could clear the Senate with only a simple majority. Most bills need60 votes to clear the Senate, where Republicans hold 52 seats.

Republicans say the law has hurt the economy by requiring companies to spend more on health care and has imposed crippling requirements and taxes that have driven up healthcare costs. They say the law is faltering amid premium increases in 2017 on the exchanges where consumer can buy policies, as well as decisions by some insurers to leave the exchanges and lower than expected enrollment.

The Obama administration said on Tuesday that a double-digit jump in premiums this year on the health law's exchanges was a one-time correction, and that a recent, brisk pace of sign-ups shows that the exchanges are on solid ground.

Senate Democrats have been united so far in resisting the GOP effort to roll back the health law, which has expanded coverage for roughly 20 million people. A large number are lower-income people who have been covered through Medicaid expansions in 31 states and the District of Columbia.

Senators debated until just after 1 a.m., with both Republican and Democratic lawmakers trying to add amendments to the resolution before it was brought to a vote. No amendments passed.

To show their opposition to the budget resolution, Democrats voted one by one from their desks on the Senate floor. Each senator stood up and called out a "no" vote, though most of the Republican lawmakers had left, and debate isn't allowed during a vote.

Senate Minority Leader Chuck Schumer (D., N.Y.) warned Republicans that they were entering a political quagmire if they proceed with their plans to repeal and replace the health law.

"If Republicans go forward with this plan, they may mollify their base, but they will ostracize and hurt the American people, and ultimately lose in the court of public opinion," Mr. Schumer said on the Senate floor.

Sen. Rand Paul of Kentucky was the only Republicanto join all of the members of the Senate Democratic caucus in opposing the budget.

Mr. Paul opposed the budget over its spending levels, which he believes add too much to the federal budget deficit.

The budget's spending levels are in line with those agreed to in a two-year budget deal reached by Congress and the Obama White House in the fall of 2015. Changing them could complicate efforts to fund the government for the final five months of the fiscal year. The government's current funding expires at the end of April. Most Republicans have said they would focus on cutting spending when they write a budget this spring for the coming fiscal year 2018.

"There is no reason we cannot repeal Obamacare and pass a balanced budget at the same time," Mr. Paul said in a statement after the vote.

GOP senators on Wednesday night withdrew an amendment that would have delayed the deadline for preparing the repeal legislation to March 3from the Jan. 27. President-elect Donald Trump has been urging Congress to move quickly to prepare legislation to repeal and overhaul the health system, though his recent messages have been mixed.

In a Twitter message last week, he warned Republicans to be careful about assuming political responsibility for dismantling the law. In a press conference Wednesday, Mr. Trump said that, once his secretary of the Department of Health and Human Services is in office, he would put forward a plan to "almost simultaneously" repeal and replace the health law.

House and Senate Republicans said that, meanwhile, they would continue the complicated procedural maneuvering that could enable them to repeal large sections of the health law.

The House is expected to vote Friday on the budget resolution in what is likely to be a largely party-line vote. However, some Republicans said they want more information about the GOP plan to repeal the healthlaw before the vote on the budget measure.

"It is a vehicle. Then the question is, 'What's in the vehicle?'" Rep. Dave Brat (R., Va.) told reporters Wednesday. Mr. Brat said he was hoping to get enough information to be able to support the budget Friday. "We all want to vote yes."

Write to Kristina Peterson at kristina.peterson@wsj.com and Natalie Andrews at Natalie.Andrews@wsj.com

(END) Dow Jones Newswires

January 12, 2017 08:44 ET (13:44 GMT)

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