WASHINGTON (Reuters) - Details of potential Obamacare replacements by U.S. House Republicans emerged in news reports on Friday, as Republican lawmakers have vowed to introduce new legislation in the coming weeks.

The federal government forms for applying for health coverage are seen at a rally held by supporters of the Affordable Care Act, widely referred to as "Obamacare", outside the Jackson-Hinds Comprehensive Health Center in Jackson, Mississippi, U.S. on October 4, 2013. REUTERS/Jonathan Bachman/File Photo

Republicans have yet to agree on a single detailed policy proposal to repeal and replace the Affordable Care Act, the signature domestic policy of former Democratic President Barack Obama.

Still to be worked out are details including the future of Medicaid, the government health insurance program for the poor that was expanded in more than 30 states under Obamacare, and how a new healthcare law would be funded.

One emerging scenario among Republicans is that the millions of people who received health coverage through the expansion of Medicaid would be “grandfathered in,” according to the Washington Post. States that did not expand Medicaid could receive more money through increased federal “disproportionate share” payments used to help hospitals that serve a large number of uninsured patients.

And a draft Republican replacement plan for Obamacare, which news outlet Politico uploaded to its website, would cap the amount of money given to states for Medicaid and end tax subsidies based on income for the purchase of individual plans in 2020.

House staffers would not comment on the authenticity of the document, which was dated Feb. 10. President Donald Trump and Republicans have said they would present a plan for repealing and replacing Obamacare in the coming weeks.

It is not clear whether there is sufficiently broad support among Republican lawmakers for all of the measures in the draft proposal, or how the plans might change as they move through congressional committees.

The draft “addresses the major issues and is a serious proposal for transitioning out of Obamacare,” said Ed Haislmaier, a senior research fellow and healthcare policy expert at the Heritage Foundation who was on Trump’s transition team.

“Clearly the details will continue to evolve and we’ll be watching as they do,” he said in an emailed statement to Reuters.

U.S. health insurance executives, many of whom have lost hundreds of millions of dollars on the Obamacare individual insurance markets, are due to meet with Trump on Monday, according to a Bloomberg report. A Blue Cross Blue Shield Association spokeswoman confirmed it was invited to the meeting and will attend.

Republicans have repeatedly pledged not to “pull the rug out” from millions of Americans who gained access to healthcare under the law, and recent polls show more respondents favoring Obamacare than opposing it.

The Kaiser Family Foundation found broad bipartisan support for maintaining federal funding for the Medicaid expansion, with 84 percent of respondents saying it was important to do so, according to a survey released on Friday. The poll also found the law has record levels of support, with more Americans now viewing it favorably than unfavorably.

“Obamacare has failed. We welcome any and all efforts to repeal and replace it that put patients first,” said Caitlin Oakley, a spokeswoman for the U.S. Department of Health and Human Services.

Democrats decried the draft proposal on Friday and said it would cause millions of Americans to lose their health insurance.

“The deeply harmful path House Republicans have laid out would spell disaster for families nationwide,” U.S. Senator Patty Murray, a Washington state Democrat, said in a statement. “President Trump, who promised families he would provide insurance for everyone, should be the first to oppose it.”