(AP)—Congressional budget analysts are now estimating that nearly 6 million Americans—most of them in the middle class—will have to pay a tax penalty for not getting health insurance once President Barack Obama's health care law is fully in place.

That's 2 million more than a previous estimate found, or a 50 percent increase. The average penalty will be nearly $1,200.

Starting in 2014, the new health care law requires virtually every legal resident of the U.S. to carry health insurance, or face a tax penalty. The Supreme Court upheld Obama's law as constitutional after finding that the penalty fell within the power of Congress to impose taxes.

The nonpartisan said Wednesday the penalty will raise $6.9 billion when fully in effect in 2016.