The hardline conservative House Freedom Caucus, which helped to sink Republicans' earlier attempt to revamp Obamacare last month, endorsed an amended plan Wednesday to replace the Affordable Care Act.

But it remains to be seen if moderate Republicans possibly wary of the new plan will get behind it and provide enough votes for passage in the House. The GOP has worked to balance the concerns of both groups in its caucus as it tries to follow through on a key campaign pledge by candidate Donald Trump.

In a statement, the Freedom Caucus said its members would support the plan if it includes the MacArthur amendment, which would allow states to waive some key Obamacare provisions. The compromise was negotiated between moderate GOP Rep. Tom MacArthur of New Jersey and Freedom Caucus leader Rep. Mark Meadows of North Carolina.

"The MacArthur amendment will grant states the ability to repeal cost driving aspects of Obamacare left in place under the original AHCA. While the revised version still does not fully repeal Obamacare, we are prepared to support it to keep our promise to the American people to lower healthcare costs," the Freedom Caucus said in a statement.

It is not clear how close the Freedom Caucus support will get the proposal to passage in the House. The group's backing puts pressure on moderate GOP members of Congress who may hesitate to back the plan.

The amendment lets states, in certain conditions, opt out of provisions to not charge customers more for pre-existing conditions and provide so-called essential health benefits.

Those pieces of the plan may irk some moderates already concerned about the estimates of health-care coverage losses under the original proposal to replace Obamacare.

Regardless of what happens in the House, efforts to repeal and replace Obamacare may face a tougher test in the Senate, where only three Republican defections can block the plan.

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