An Obamacare fund that Republicans criticized as a "bailout" ofinsurance companies has resurfaced as a similar provision in theSenate GOP’s health care plan -- though this time the objectionsare more muted.

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The new bill’s $50 billion market-stability fund is intended toprotect insurers that cover large numbers of customers withmore-costly health problems from having to raise their premiums forthe next four years.

It’s much like an Affordable Care Act provision known as riskcorridors that drew Republican fire. In December 2014, amid a pushby Senator Marco Rubio of Florida, Congress tacked a provision ontoa spending bill limiting the funds that could be paid to insurerswith customers who require more expensive care.

Jesse Lee, a former aide to President Barack Obama, labeled it"one of the great acts of ACA sabotage."

There’s "no difference" between the insurer funds in Obamacareand the ones in the Senate Republican bill, said Sara Rosenbaum, aprofessor of health law at George Washington University.

Tim Jost, a health policy specialist and professor emeritus atthe Washington and Lee University School of Law, said the provisionis not a bailout but rather a policy designed "to reduce thereluctance of insurers to take on high-cost enrollees and make itmore attractive for them to do so."

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Jost said Democrats didn’t include enough reinsurance andstability funds in the Affordable Care Act and they "phased outreally quickly," causing premiums to rise.

During his 2016 presidential campaign, Rubio touted his role inrestricting the insurer funds. "When they passed Obamacare, theyput a bailout fund in Obamacare," he said in a GOP primary debateon Feb. 25, 2016, arguing that lobbyists "put a bailout fund in thelaw that would allow public money to be used, taxpayer money, tobail out companies when they lost money."

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Asked Monday if he has similar concerns about the insurer fundsin the Republican health-care bill, Rubio said he’s reviewing theprovision.

"The stabilization fund is a transitionary fund," Rubio said. "Ineed to see how it’s funded, where the money’s coming from and howit’s being appropriated. But I need to learn more about it. I dohave some concern, no doubt."

The bill -- H.R. 1628, drawn up without any public hearings bySenate Majority Leader Mitch McConnell of Kentucky -- includes $15billion a year in market-stabilizing funds over the next two yearsand $10 billion a year in 2020 and 2021. McConnell had hoped thefull Senate would vote on the measure this week, but he was forcedto delay consideration for lack of support among his fellowRepublicans.

Rand Paul, Mike Lee

Cries of a "bailout" under the McConnell bill’s insurer fundhave been limited to conservative senators such as Rand Paul ofKentucky and Mike Lee of Utah. Top Republicans are defending theprovision as important to make insurance affordable.

"The stabilization fund is important to keep premiums down andcopays and deductibles reasonable," Senator Lamar Alexander ofTennessee, the chairman of the health committee, said Wednesday inan interview. "It’s helping people with less money afford to buyinsurance."

Senator Mike Crapo of Idaho said Wednesday he supports thestabilization fund in the GOP bill and would vote for themeasure.

Senator Michael Bennet, a Colorado Democrat, said Republicanswho are pushing the stabilization fund "may have discovered howmuch damage they did when they stripped out the risk corridors fromthe Affordable Care Act."

"That’s one of the things about this debate that’s soinfuriating -- the things that they blame on Obamacare areactually, in this case, things that opponents of Obamacare passed,"he said in an interview Wednesday.