Story highlights Republicans challenged some Obamacare payments in court and won, but now are faced with making those same payments

They must update the court next Tuesday

Washington (CNN) Three years ago, House Republicans sued the Obama White House to block the administration from diverting funds to pay health care insurers to help cover low-income Americans.

They won the lawsuit and now control the White House and Congress. But that means they're facing a deadline to determine how they will do what they sued to stop: spending taxpayer money to insurers to subsidize insurance for low-income Americans.

Republican leaders are acknowledging that in order to keep the Obamacare marketplace from collapsing on their watch, they will need to allocate billions of dollars in what are known as cost-sharing reduction payments. They also have to act fast -- they need to update the judge in the lawsuit Tuesday — and figure out how to placate insurers and skeptical conservatives.

The payments are at the center of a contentious 2014 lawsuit the House filed against the Obama administration. Back then, Republicans were trying to gut the Affordable Care Act in whatever way they could with Obama still in the White House. The House argued that that the cost-sharing reduction payments were illegal because Congress --- not the executive branch -- had control over allocating spending, and Congress had not appropriated the money.

Now that they're on the verge of repealing Obamacare, Republican members are cautious about any disruptions that could hit the marketplace on their watch.

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