Democrats responded with fury on Friday night after a federal judge in Texas ruled that key provisions in the Affordable Care Act, otherwise known as "Obamacare," were unconstitutional — rendering the entire law unconstitutional.

Some conservative groups praised the ruling, while other Republican lawmakers stayed silent.

The federal judge ruled the individual mandate was unconstitutional, and that because it is "essential to and inseverable from the remainder of the ACA," the entire law is invalid.

Here are some initial reactions from lawmakers and organizations.

Democrats responded with fury on Friday night after a federal judge in Texas ruled that key provisions in the Affordable Care Act, or "Obamacare," were unconstitutional — rendering the entire law unconstitutional.

Meanwhile in a tweet, President Donald Trump called for Congress to to pass a "STRONG" health care bill, and some conservative organizations and lawmakers praised the judge's decision.

US District Judge Reed O'Connor in the Northern District of Texas sided with 19 states led by Texas who argued that the individual mandate — the requirement that everyone must have health insurance — was unconstitutional after lawmakers repealed the tax penalty for not having insurance. Fourteen states and the District of Columbia were arguing in favor of the law.

The Trump administration sided with the 19 states' individual mandate argument, but also argued to keep some provisions of the bill, including Medicaid expansion and the health exchanges, according to Bloomberg.

The judge ruled the individual mandate was unconstitutional, and because it is "essential to and inseverable from the remainder of the ACA" the entire law is invalid.

The ruling could impact millions of Americans, including those with preexisting conditions. Since there is no injunction from the court, it is possible, one expert tweeted, that the law could stay in place while the ruling is appealed — and lawmakers like House Minority Nancy Pelosi have stated that the decision would be appealed.

Lawmakers and attorneys general quickly responded. Here are some initial reactions:

President Donald Trump via Twitter: "As I predicted all along, Obamacare has been struck down as an UNCONSTITUTIONAL disaster! Now Congress must pass a STRONG law that provides GREAT healthcare and protects pre-existing conditions. Mitch and Nancy, get it done!"

"As I predicted all along, Obamacare has been struck down as an UNCONSTITUTIONAL disaster! Now Congress must pass a STRONG law that provides GREAT healthcare and protects pre-existing conditions. Mitch and Nancy, get it done!" House Minority Leader Nancy Pelosi: "While the district court’s absurd ruling will be immediately appealed, Republicans are fully responsible for this cruel decision and for the fear they have struck into millions of families across America who are now in danger of losing their health coverage. When House Democrats take the gavel, the House of Representatives will move swiftly to formally intervene in the appeals process to uphold the life-saving protections for people with pre-existing conditions and reject Republicans’ effort to destroy the Affordable Care Act."

"While the district court’s absurd ruling will be immediately appealed, Republicans are fully responsible for this cruel decision and for the fear they have struck into millions of families across America who are now in danger of losing their health coverage. When House Democrats take the gavel, the House of Representatives will move swiftly to formally intervene in the appeals process to uphold the life-saving protections for people with pre-existing conditions and reject Republicans’ effort to destroy the Affordable Care Act." Senate Minority Leader Chuck Schumer: "If this awful ruling is upheld in the higher courts, it will be a disaster for tens of millions of American families, especially for people with pre-existing conditions. The ruling seems to be based on faulty legal reasoning and hopefully it will be overturned. Americans who care about working families must do all they can to prevent this district court ruling from becoming law."

"If this awful ruling is upheld in the higher courts, it will be a disaster for tens of millions of American families, especially for people with pre-existing conditions. The ruling seems to be based on faulty legal reasoning and hopefully it will be overturned. Americans who care about working families must do all they can to prevent this district court ruling from becoming law." Sen. Bernie Sanders via Twitter: " This is an outrageous, disastrous decision that threatens the health care and lives of millions of people. It must be overturned. We must move forward to make health care a right for every American."

" Sen. Sherrod Brown: "This decision threatens the health coverage of 20 million people and undermines pre-existing condition protections for all Americans. We cannot go back to the days when insurance companies could deny coverage for people who are sick. We will fight back,” said Brown. “Enrollment is still open through Saturday and no one should be intimidated by this ruling. You can still get coverage by going to www.healthcare.gov or calling 1-800-318-2596 by Saturday."

"This decision threatens the health coverage of 20 million people and undermines pre-existing condition protections for all Americans. We cannot go back to the days when insurance companies could deny coverage for people who are sick. We will fight back,” said Brown. “Enrollment is still open through Saturday and no one should be intimidated by this ruling. You can still get coverage by going to www.healthcare.gov or calling 1-800-318-2596 by Saturday." Sen. Chris Murphy: "This is a five alarm fire -- Republicans just blew up our health care system. The anti-health care zealots in the Republican Party are intentionally ripping health care away from the working poor, increasing costs on seniors, and making insurance harder to afford for people with preexisting conditions,” said Murphy."

"This is a five alarm fire -- Republicans just blew up our health care system. The anti-health care zealots in the Republican Party are intentionally ripping health care away from the working poor, increasing costs on seniors, and making insurance harder to afford for people with preexisting conditions,” said Murphy." Sen. Dick Durbin: "Today’s decision by a district court judge — backed by President Trump — is politics at its worst and threatens access to care for millions of Americans with pre-existing conditions. But this misguided decision will be appealed, and I am confident that common sense will prevail. Americans across the country should continue to sign up for health insurance through Saturday’s deadline."

"Today’s decision by a district court judge — backed by President Trump — is politics at its worst and threatens access to care for millions of Americans with pre-existing conditions. But this misguided decision will be appealed, and I am confident that common sense will prevail. Americans across the country should continue to sign up for health insurance through Saturday’s deadline." Sen Ron Wyden: "Today’s ruling is an assault on all Americans’ basic health care rights and judicial overreach at its worst,” Wyden said. “Trump and Republicans in Congress will achieve their long-sought goals if this ruling stands: the elimination of pre-existing condition protections and Medicaid coverage for millions of vulnerable Americans. Seniors will pay more for their prescriptions and middle-class families will lose tax breaks that keep their health care affordable. This judge chose to deliver his ruling the day before the end of open enrollment - a deliberate, ideological move to sabotage the Affordable Care Act at the expense of families’ health care. If you or your loved ones need health care, you should still sign up as planned at Healthcare.gov before the open enrollment deadline at end of the day tomorrow despite this attempted sabotage."

"Today’s ruling is an assault on all Americans’ basic health care rights and judicial overreach at its worst,” Wyden said. “Trump and Republicans in Congress will achieve their long-sought goals if this ruling stands: the elimination of pre-existing condition protections and Medicaid coverage for millions of vulnerable Americans. Seniors will pay more for their prescriptions and middle-class families will lose tax breaks that keep their health care affordable. This judge chose to deliver his ruling the day before the end of open enrollment - a deliberate, ideological move to sabotage the Affordable Care Act at the expense of families’ health care. If you or your loved ones need health care, you should still sign up as planned at Healthcare.gov before the open enrollment deadline at end of the day tomorrow despite this attempted sabotage." Sen. Joe Manchin: "This misguided and inhumane ruling will kick millions of Americans and tens of thousands of West Virginians off of their health insurance. West Virginians with pre-existing conditions will be at risk of losing their health insurance. And the thousands of West Virginians who gained health insurance through the Medicaid expansion will no longer qualify. This ruling is just plain wrong. I look forward to its appeal to a higher court, and I intend to fight to ensure that the Senate has an opportunity to intervene to defend these critical health safeguards. I urge West Virginia’s Attorney General to withdraw from this dangerous lawsuit on behalf of the tens of thousands of West Virginians who will be harmed."

"This misguided and inhumane ruling will kick millions of Americans and tens of thousands of West Virginians off of their health insurance. West Virginians with pre-existing conditions will be at risk of losing their health insurance. And the thousands of West Virginians who gained health insurance through the Medicaid expansion will no longer qualify. This ruling is just plain wrong. I look forward to its appeal to a higher court, and I intend to fight to ensure that the Senate has an opportunity to intervene to defend these critical health safeguards. I urge West Virginia’s Attorney General to withdraw from this dangerous lawsuit on behalf of the tens of thousands of West Virginians who will be harmed." House Majority Whip: "When Democrats forced Obamacare down the throats of the American people on a purely partisan basis, they threatened that the law needed to be passed so that people could find out what was in it. Over the last eight years since it was signed into law, we have found out that the Democrats who passed it caused millions of families to lose the plans and doctors they liked, and imposed unaffordable premiums and deductibles that undermine the basic coverage that families enjoy. Not only does tonight's ruling confirm that this broken law cannot hold up under court scrutiny, but it also affirms that the law does not actually protect people with preexisting conditions."

Organizations also weighed in

American Medical Association President Barbara L. McAneny, M.D. : "Today’s decision is an unfortunate step backward for our health system that is contrary to overwhelming public sentiment to preserve pre-existing condition protections and other policies that have extended health insurance coverage to millions of Americans. It will destabilize health insurance coverage by rolling back federal policy to 2009. No one wants to go back to the days of 20 percent of the population uninsured and fewer patient protections, but this decision will move us in that direction."

"Today’s decision is an unfortunate step backward for our health system that is contrary to overwhelming public sentiment to preserve pre-existing condition protections and other policies that have extended health insurance coverage to millions of Americans. It will destabilize health insurance coverage by rolling back federal policy to 2009. No one wants to go back to the days of 20 percent of the population uninsured and fewer patient protections, but this decision will move us in that direction." Joint statement from the American Cancer Society Cancer Action Network, American Diabetes Association, American Heart Association, American Lung Association and National Multiple Sclerosis Society: "This decision threatens to resurrect barriers to health care for people with serious illnesses including cancer, heart disease, stroke, lung disease, diabetes and those with neurological conditions. If the ruling stands, anyone with a pre-existing condition could be charged more for health coverage or denied access to coverage altogether. Health plans would no longer be required to offer essential benefits necessary to prevent and treat a serious condition and could once again impose arbitrary annual and lifetime limits on coverage. Invalidating the law also would jeopardize the federal tax credits that make health insurance affordable for more than 8 million Americans, threatening their access to critical health coverage."

"This decision threatens to resurrect barriers to health care for people with serious illnesses including cancer, heart disease, stroke, lung disease, diabetes and those with neurological conditions. If the ruling stands, anyone with a pre-existing condition could be charged more for health coverage or denied access to coverage altogether. Health plans would no longer be required to offer essential benefits necessary to prevent and treat a serious condition and could once again impose arbitrary annual and lifetime limits on coverage. Invalidating the law also would jeopardize the federal tax credits that make health insurance affordable for more than 8 million Americans, threatening their access to critical health coverage." Think tank FreedomWorks: "Although Republicans in Congress have failed to repeal Obamacare in its entirety, this ruling has proven that their action to repeal the individual mandate in last year’s tax reform legislation was a consequential move. FreedomWorks agrees with the Judge O’Connor’s ruling that Obamacare is unconstitutional."

"Although Republicans in Congress have failed to repeal Obamacare in its entirety, this ruling has proven that their action to repeal the individual mandate in last year’s tax reform legislation was a consequential move. FreedomWorks agrees with the Judge O’Connor’s ruling that Obamacare is unconstitutional." Heritage Action Executive Director Time Chapman: "Americans should not fall for the tired myth from Democrats that only Obamacare protects pre-existing conditions. If Congress returns control of health care back to the states, it will give more Americans, even those with pre-existing conditions, greater access to affordable health care."

The deadline to enroll for coverage on Healthcare.gov is Saturday, December 15.