(CNN) Republicans warned seven years ago that a health care law passed only by Democrats -- with no support from the other party -- would struggle to survive. The party-line vote to pass Obamacare, they said, was arrogant and reckless.

Now, the GOP is in charge, and poised to run afoul of its own warnings.

As Republican lawmakers begin to dismantle President Barack Obama's landmark health care law, awaiting the inauguration of President-elect Donald Trump, they face the prospect of overhauling the American health insurance system without any help from across the aisle. Democrats appear increasingly determined to offer Trump's party as little help as possible.

GOP efforts to revamp the Affordable Care Act -- some 20 million people are covered through Obamacare while many more have been less directly impacted by the law -- are poised to disrupt millions of Americans' health insurance. If repealing and replacing the ACA ultimately becomes a purely partisan Republican exercise, Obamacare could emerge one of the biggest political liabilities for Trump and his party -- just as it became a problem for Democrats.

Republicans sought to paint the Democrats' passing Obamacare without GOP support as extreme. Democrats are happy to return the favor. Making the difficult task of enacting healthcare reform a millstone for Republicans could end up helping Democrats in the 2018 midterm elections

Former Health and Human Services Secretary Mike Leavitt, a Republican, said an overhaul of Obamacare would only have "long-term viability" if the GOP can win support from Democratic lawmakers.

"The GOP has indicated publicly that they intend not to make the same mistake that the Democrats did in passing a bill that was not supported in a bipartisan way," Leavitt said. "I think that's wise."

But Democratic votes won't be easy to get. In a Capitol Hill pep talk Wednesday, Obama urged Democrats not to "rescue" Republicans by helping them pass replacement measures, according to sources in the room.

After the meeting, a White House aide said Obama used "Trumpcare" as an indication he was open to Trump taking credit for improvements.

That is, of course, if Democrats see any changes they like.

Sen. Dick Durbin, the second-ranking Democrat in the chamber, told CNN that Republicans would be making a serious mistake by moving ahead with reforming Obamacare on a purely partisan basis. Durbin went as far as to criticize Republicans for refusing to partner with Democrats on making incremental improvements to Obamacare over the years.

"We've had six years of opportunities to work together on a bipartisan basis to improve or change the Affordable Care Act. They have never, ever, accepted an invitation for that," Durbin said. "Their approach is: repeal it, and once you've repealed it, then we'll think of something new. That's not a responsible approach."

Not that Obama and Democrats didn't try. After Obama took office in 2009, his administration's initial efforts to win over Republican support for healthcare reform went nowhere as one by one, potential GOP allies turned their backs -- and Republican leaders were happy to paint the law as single party over-reach. The healthcare reform bill that landed on the president's desk in March 2010 had not received support from a single GOP lawmaker in the House or Senate.

"The ACA stands in contrast to just about every other piece of major social welfare legislation in the history of this county, which is usually done with bipartisan support," said Tevi Troy, deputy secretary of Health and Human Services under President George W. Bush.

GOP Rep. Phil Roe, a physician who last week introduced a repeal and replace Obamacare bill in the House, said the law was a "disaster" in large part because Democrats passed it without GOP input.

"I never understood why healthcare is Republican or Democrat issue. I've never seen a Republican or Democrat heart attack in my life," Roe said. "There were nine physicians in the Doctors Caucus at that time. Not one of us was asked one thing about that healthcare bill."

Well before the law was passed, Republicans have used promises to block then repeal Obamacare -- a phrase the GOP started using as a pejorative -- as a political rallying cry to rev up the party's base

And now that the GOP has the opportunity to dismantle Obamacare, there is no expectation that the party will garner any support from Democrats.

In fact, the vehicle that Republicans are using to roll back major pieces of the law -- a budget resolution followed by a budget reconciliation bill -- is a fast-track process that will allow the GOP to avoid a potential Democratic filibuster in the Senate.

But when it comes to the second and much more complicated task of overhauling Obamacare -- replacing what gets repealed -- Republicans don't yet have a plan.

GOP leaders have so far indicated a preference for the "repeal and delay" approach: passing a repeal bill as soon as possible but delaying the repeal measures from going into effect for several years as they develop a measure to replace the law. But already, rank-and-file Republicans are expressing reservations about moving too fast on repeal when there is little clarity on replace -- and creating a potential political nightmare

Department Health and Human Services Secretary Sylvia Mathews Burwell will warn Congress of the dangers of repeal without replace during a speech Monday in Washington.

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"If the Affordable Care Act is repealed without a replacement, the damage to the country's individual insurance market will begin this spring," Burwell will say, according to excerpts. "If health insurance companies don't know what the market will look like going forward, many will either raise prices or drop out. That means more Americans won't be able to afford coverage, and others won't be able to find it at all."

In a sudden role reversal, Republicans are now labeling Democrats obstructionists when it comes to the healthcare law.

"I think it's very unfortunate that (Senate Minority Leader) Chuck Schumer has essentially said he's not interested in cooperating," GOP Sen. John Barrasso told CNN in an interview.

Barrasso and his fellow Republicans -- including the President-elect -- are also pressuring Democrats to cooperate.

"It is time for Republicans & Democrats to get together and come up with a healthcare plan that really works - much less expensive & FAR BETTER!" Trump tweeted last week.

...time for Republicans & Democrats to get together and come up with a healthcare plan that really works - much less expensive & FAR BETTER! — Donald J. Trump (@realDonaldTrump) January 5, 2017

Democrats vehemently oppose repealing Obamacare, and only a handful of lawmakers -- moderates and those hailing from conservative areas -- are likely to show a willingness to discuss replacement efforts with Republicans.

Sen. Joe Manchin of West Virginia, a moderate Democrat, declined to attend Obama's meeting on Capitol Hill with Democrats last week because he said he opposes any purely partisan conversations about Obamacare.

"I would just caution my friends on the Republican side: the division we've seen in the country is because we had a bill that was passed in 2009 ... without any bipartisan support and now it's about to be repealed without any bipartisan support." Manchin told CNN. "You gotta be careful, throwing the baby out with the bathwater."