An assortment of tax increases, health industry fees and Medicare cuts will help pay for the changes.
Still, not everyone will be covered
An estimated 26 million people will remain without coverage once the law is fully implemented, including illegal immigrants, people who don't sign up and choose to face the fines instead, and those who can't afford it even with the subsidies. That number could be higher, depending on whether any states refuse the Medicaid expansion.
The taxing truth
When the law was before Congress, Obama and Democrats avoided calling its penalty for going uninsured a "tax." But the administration argued before the Supreme Court that the law was constitutional as a federal tax. The court rejected two other Obama administration arguments for the law but accepted the tax one.
In 2016, after the law is fully in place, about 4 million people will pay the penalty to the Internal Revenue Service for being uninsured, the Congressional Budget Office has estimated. They would pay $695 per uninsured adult or 2.5 percent of family income, up to $12,500 per year.
The IRS can't prosecute violators or place liens against them, however. Its only enforcement option may be withholding money from refunds.
What are Republicans saying?
"Obamacare was bad law yesterday. It's bad law today," Romney said after the ruling.
The Republican-led House already has voted for repeal but can't push it forward so long as Obama's in the White House and Democrats lead the Senate — making the November elections crucial.
Senate Republican Leader Mitch McConnell called the court decision "a fresh start on the road to repeal."
Obama says the decision upholds the fundamental principle that in the wealthiest nation on earth, no one should be ruined financially by an illness or accident.
He called it "a victory for people all over this country whose lives will be more secure because of this law."
About that mandate
Many parts of the law have proven popular. But the insurance mandate is widely disliked.
Each time AP has asked in polls, more than 8 in 10 Americans have said the government should not have the right to require everyone to buy health insurance.
The public also has tilted against the law as a whole over the two years since it was passed. About half opposed it and a third were in favor in an AP-GfK poll shortly before the Supreme Court ruled.
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