Republicans revived their calls to replace Obamacare in the wake of a federal judge declaring the healthcare law unconstitutional, but Democrats indicated they had no plans to abandon the legal battle ahead.

Obamacare remains the law of the land, but faces some level of uncertainty as it makes its way through the courts. On Friday night, U.S. District Judge Reed O’Connor in the Northern District of Texas ruled that all of Obamacare should be thrown out because the penalty on the uninsured, known as the "individual mandate," was set to be zeroed out in 2019 as a result of the Republican-backed tax law passed last year.

For Democrats, this means more time in court. California Attorney General Xavier Becerra has vowed to appeal the ruling, calling it "misguided," and other Democratic-led states are expected to join him. Chuck Schumer, the Senate minority leader, said he hoped the ruling would be overturned, and Nancy Pelosi, the favored House Speaker for the next Congress, said the House would "swiftly intervene" in the appeals process.

[Trump: Congress can make healthcare 'great' after judge struck down Obamacare]

The case is likely to be appealed to the U.S. Court of Appeals for the 5th Circuit in New Orleans, and from there, it may go before the Supreme Court. Sarah Sanders, the White House press secretary, said Friday night that she expected it would land before the high court.

“The judge’s decision vindicates President Trump’s position that Obamacare is unconstitutional," she said. "Once again, the president calls on Congress to replace Obamacare and act to protect people with pre-existing conditions and provide Americans with quality affordable healthcare."

The actions in the courts are another way that Republicans are aiming to undo the law. The latest ruling follows a slew of challenges Obamacare has faced both in Congress and in the courts since it passed.

Republicans failed to repeal Obamacare in 2017, and Democrats have largely said they believe they won the House this past midterm election because of those GOP efforts. A Senate bill had come together to help shore up Obamacare, but in the end it evaporated over a disagreement about anti-abortion language. GOP bills have aimed to keep certain popular parts of the law in place, including rules to guarantee coverage for people with pre-existing illnesses, but critics have said the provisions have been weaker than those in Obamacare and would make coverage unaffordable.

Obamacare, formally known as the Affordable Care Act, passed in 2010 without a single Republican vote, and its provisions have gone before the Supreme Court multiple times. Certain parts of the law have stood while other parts have been rejected or weakened. Under Trump, the high court has a more conservative bench following his appointments of Justices Neil Gorsuch and Brett Kavanaugh.

Following the latest decision by the federal judge, Republicans said it was time to revive talks about new legislation. House Ways and Means Committee Chairman Kevin Brady, R-Texas, called the decision "not surprising." He said that if the courts ultimately uphold the decision then both parties should "start over" on healthcare, while keeping popular protections in place including allowing children to stay on their parents' healthcare plan until age 26.

Energy and Commerce Committee Chairman Greg Walden, R-Ore., echoed the calls for new legislation.

"We have a rare opportunity for truly bipartisan healthcare reform," he said.

The case, Texas v. Azar, was brought by 20 GOP state officials who argued Obamacare should be thrown out because of the zeroing out of the individual mandate. The Trump administration sided with the officials, but said that only the rules on pre-existing illnesses should go, while the rest of the law should remain intact.

O'Connor in his decision sided with Republican officials, saying that Obamacare's backers have since the law's inception argued that the mandate could not be severed from the rest of its provision. He further argued that the Supreme Court had once upheld the mandate on the basis of Congress having the power to tax, but now the tax was set to go away.

O'Connor's decision came just one day before the end of open enrollment, the period during which people are allowed to sign up for healthcare plans with subsidies from the federal government. The Centers for Medicare and Medicaid Services, the agency that operates this part of the law, said enrollment was still underway despite the ruling.

“The recent federal court decision is still moving through the courts, and the exchanges are still open for business and we will continue with open enrollment," a spokesperson said. "There is no impact to current coverage or coverage in a 2019 plan.”