Obama: Affordable Care Act is 'here to stay'

President Barack Obama said his landmark health care law is "here to stay" after it survived its second major legal challenge Thursday.

"This law is working. And it's going to keep doing just that," Obama said in a press conference.

The Supreme Court ruled in a 6-3 decision Thursday that federal subsidies—which help nearly 6.4 million people pay for their Obamacare health plans—are legal under the Affordable Care Act. A pillar of Obama's first campaign and tenure in office, the law was designed to reduce the number of uninsured Americans.

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"This not an abstract thing anymore. This is not a set of talking points. This is reality. We can see how the law is working. It works exactly as it is supposed to," he said.

The latest decision exacerbated the political tension surrounding the health law. Reactions immediately came from both Obama's Democratic and the opposition Republican Party, with officials looking ahead to how the 2016 presidential election could affect U.S. health care.

In a press conference, House Speaker John Boehner (R-OH) said the ruling does not change a "fundamentally broken" system. He added that Republicans will continue efforts to repeal the law and "put the American people back in charge of their own health care."

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President Barack Obama, flanked by Vice President Joe Biden, gives a statement on the Supreme Court health care decision in the Rose Garden at the White House on June 25, 2015 in Washington.
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President Barack Obama, flanked by Vice President Joe Biden, gives a statement on the Supreme Court health care decision in the Rose Garden at the White House on June 25, 2015 in Washington.

The case known as King v. Burwell was the latest challenge to Obama's health care law. Since its passage in 2010, the ACA has withstood numerous congressional attempts to repeal and a previous Supreme Court case.

A win for Thursday's plaintiffs—who argued that only customers of state exchanges can receive the financial boost—could have disrupted coverage for up to 8 million people in states served by the federal insurance marketplace by next year.

"Congress passed the Affordable Care Act to improve health insurance markets, not to destroy them," Chief Justice John Roberts wrote in the majority decision. Joining Roberts in the majority were Justices Anthony Kennedy, Ruth Bader Ginsburg, Stephen Breyer, Sonia Sotomayor and Elena Kagan.

Conservative Justice Antonin Scalia, in his dissent to the decision, called the majority decision "absurd." He wrote that Roberts' opinion "changes the usual rules of statutory interpretation for the sake of the Affordable Care Act."

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After the decision Thursday, the Republican Party maintained its official stance that the government has overreached with the law. In a statement, Republican National Committee Reince Priebus contended that the U.S. needs a leadership overhaul to "fix our broken health care system."

Obama refuted those claims on Thursday.

"This has never been a government takeover of health care," he said.

House Minority Leader Nancy Pelosi (D-CA) on Thursday called the decision "a victory for common sense and for all American families." She called on Republicans to "abandon their assault" on the ACA.

— CNBC's Dan Mangan contributed to this report