An overwhelming majority of people disapprove of Republican lawmakers' plan to repeal the Affordable Care Act without having a ready replacement for the health care law, according to a poll released Friday.

And judging by the letter-writing and lobbying in the first week of the new congressional session, many health care and business groups agree.

A poll released Friday by the Kaiser Family Foundation finds that 75 percent of Americans say they either want lawmakers to leave Obamacare alone, or repeal it only when they can replace it with a new health care law. Twenty percent of those polled say they want to see the law killed immediately.

But Drew Altman, CEO of the Kaiser Family Foundation, says the poll shows lawmakers don't have a strong mandate to repeal Obamacare.

"Most of the American people said they're either against repealing it or they're against repealing it unless Republicans put a replacement plan on the table," Altman says. "They want to see what comes next before they seen the ACA repealed."

Americans are about equally divided over whether Congress should repeal Obamacare, the poll shows. But of the 48 percent who want the law rolled back, about 60 percent want lawmakers to wait until they have an alternative plan.

And Obamacare isn't even people's top health care concern. The vast majority — 67 percent — say their top priority is finding a way to lower their health care costs.

The poll findings come just days after Republicans in the Senate took the first step toward repealing President Obama's signature health care law. They voted on Wednesday to move ahead with a budget resolution that will allow them to take funding away from Obamacare, which will effectively gut the law because the subsidies to buy insurance, and the penalties for not doing so, will disappear.

Republicans say they intend to vote on repeal, but give the law time to sunset while they come up with a replacement that will give the millions of people covered under Obamacare access to insurance through some other vehicle.

On Thursday, House Speaker Paul Ryan, R-Wis., said the replacement legislation would pass by the end of the year.

But doctors, hospital groups, insurers and analysts are skeptical of that strategy. In letters, press releases and advertising campaigns, many organizations have made it clear that they want to see a replacement for the Affordable Care Act in place, or at least outlined, before Congress repeals the current law.

A report released Dec. 6 by the American Hospital Association and Federation of American Hospitals warned that a repeal could cost hospitals hundreds of billions and said "any reconsideration of the ACA should be accompanied at the same time by provisions that guarantee similar coverage to those who would lose it."

A letter sent Tuesday from the American Medical Association urged lawmakers to release details of their Obamacare replacement before repealing the current law.

"Patients and other stakeholders should be able to clearly compare current policy to new proposals so they can make informed decisions about whether it represents a step forward in the ongoing process of health reform," the letter said.

Dr. Andrew Gurman, president of the American Medical Association, says people should be able to evaluate the proposed Obamacare replacement before the current law is thrown out.

"People in this country need to understand what it is they're being asked to substitute for what's there now so they can have an informed opinion about whether it's better or not," Gurman says.

And repeal and delay?

"We have a concern that that creates uncertainty in insurance markets and uncertainty in people about whether they're going to have continuity of coverage," Gurman adds.

He says he and his members talk with lawmakers regularly.

A separate study released Thursday projects that a straight repeal of the law could kill 3 million jobs across the country by 2021.

That study, by the Milken Institute School of Public Health at George Washington University, finds that about a third of those lost jobs would come from health care, and the rest would be in other industries such as retail, construction, finance and insurance. Total business output could be cut by as much as $2.6 billion over four years, the report says. California, Florida and Texas would be most affected.

Leighton Ku, the report's lead author, says the debate over ACA repeal has focused almost completely on insurance coverage and has ignored the broader economic impact.

"The payments you make to health care then become income for workers and income for other businesses. And this spreads out," Ku says. "Health care is almost a fifth of the US economy, so as you begin to change health care, there are repercussions that go across all sectors."

Ku says he can't estimate what economic impact Obamcare replacement would have because Republicans have yet to lay out their plans.

"It's a mystery," he says.

Editor's note: The Kaiser Family Foundation supports Kaiser Health News, an editorially independent program that produces news reports heard on NPR and published onNPR.org.

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