Republican lawmakers have tried repeatedly to overturn Obamacare since the health law’s passage in 2010. But be careful what you wish for.
From 20 January, the party will control the White House and both chambers of Congress for the first time in a decade.
Now their electoral base expects them to act.
Will they finally be able to undo President Obama’s signature domestic policy achievement under a Trump presidency?
Remind me, what is Obamacare?
The Patient Protection and Affordable Care Act aims to decelerate the growth of US health spending, which is the highest in the world.
Obamacare is kept solvent by an individual mandate that requires Americans who do not receive medical insurance through their employers, or free healthcare from the government, to buy such coverage through government-run websites.
The programme offers subsidies to make health insurance more affordable and aims to reduce the cost of such policies by bringing younger, healthier people into the medical coverage system.
Obamacare also requires businesses with more than 50 full-time employees to offer health insurance.
Why is it so controversial?
There are more than 20 million Americans who now have health insurance under the law.
But the programme has been rocked over the past year by premium hikes and a trio of national insurers abandoning the online marketplaces.
Its individual mandate is unpopular because many uninsured Americans who end up paying tax penalties are low-to-moderate income workers juggling rent, car payments or student loans.
But the law is popular, too, because it bans insurance companies from denying health coverage to people with pre-existing health conditions and allows young people to remain on their parents’ plans until age 26.
Obamacare has also defied Republican predictions that it would bloat government expenditure – the Congressional Budget Office says repealing the bill would increase the federal budget deficit by $137bn (£112bn) by 2025.
Can it be repealed?
Since Republicans do not have the votes needed to repeal Obamacare outright, they are taking steps to dismantle the law through a special budget strategy.
A week before Mr Trump’s inauguration, Congress launched a budget resolution to overhaul the health law.
The measure orders Capitol Hill committees to write budget reconciliation legislation that would demolish major provisions of the bill and starve it of funding.
Congress could eliminate federal subsidies, overturn a raft of Obamacare-related taxes, and gut funding to expand Medicaid, a federal healthcare programme for low-income Americans.
Still, there may be limits to what the newly empowered Republicans can achieve in the face of a unified Democratic opposition.
Conservatives’ long-cherished dream of abrogating Obamacare could be doomed to falter in a legislative, intra-party and bureaucratic quagmire.
So what can Democrats do?
The budget reconciliation bill only requires a simple majority to pass in both the House and the Senate.
So if Republicans all stick together – and that could be a big “if” – Democrats don’t have the seats to stop them.
But Democrats will be holding the cards if and when lawmakers across the aisle get round to proposing replacement legislation.
Republicans do not have enough votes to ram through a new bill, which Democrats could filibuster indefinitely.
What’s the timeline here?
The Republican leadership wants repeal legislation drafted by 27 January, and a congressional vote on the ensuing budget reconciliation bill a month later.
Mr Trump has said he wants Obamacare repealed and replaced “essentially simultaneously”, but that wouldn’t be feasible by February, if ever.
Republicans have been touting a transition period because they’re wary of pulling the rug from under the feet of the 22 million people currently covered by the health law.
One proposal the party leadership seemed to be coalescing around was repeal-and-delay, that is, overturning Obamacare and letting it stand for up to three years while an alternative is crafted.
But many Republican lawmakers have expressed strong reservations about getting rid of the health law without an adequate replacement.
What can Trump do?
If he decides to toss a monkey wrench into the cogs of Obamacare, Mr Trump doesn’t even have to wait for Congress.
He could do it with a stroke of a pen.
As president, he could simply drop the federal government’s appeal against a lawsuit, House v Burwell, which Republican House of Representatives members won in April 2016.
That legal action argued the Obama administration was unconstitutionally spending money that Congress had not formally appropriated by reimbursing health insurers who provide coverage to low-income policyholders.
If Mr Trump opts to drop the government’s challenge, insurers who are currently giving deep discounts to half their customers would lose their reimbursements. And that, say analysts, would send Obamacare into a death spiral.
So Trumpcare here we come?
Few details have been forthcoming on what would replace Obamacare and although Republicans have bandied around lots of ideas, there seems little consensus on the way forward.
Most conservative proposals bear a resemblance to Obamacare, but with more costs shifted to consumers and fewer people covered.
One repeal bill passed by House Republicans last year – and vetoed by President Obama – would have eliminated the individual mandate.
Most Republican plans call for preserving – in some form – Obamacare’s ban on insurers denying coverage for pre-existing conditions.
Other ideas call for partially privatising Medicare, the government healthcare scheme for the elderly, or stripping funding from Planned Parenthood, the family planning group that provides abortions.
Whatever conservative lawmakers do, they’ll be mindful of political ramifications and the so-called Pottery Barn rule – If you break it, you own it.
