The White House on Monday dismissed as "overreaching" a federal judge's ruling in Florida that President Obama's sweeping health care reform law is unconstitutional and should be struck down. "We don't believe this kind of judicial activism will be upheld, and we are confident that the Affordable Care Act will ultimately be declared constitutional by the courts," Stephanie Cutter, deputy senior advisor, said on the administration's blog.

U.S. District Judge Roger Vinson, ruling on a lawsuit brought by 26 states, tossed out health care reform, calling its requirement that nearly all Americans buy health insurance or face financial penalties "a bridge too far." A federal judge in Virginia ruled against the same mandate in December but stopped short of declaring the entire law unconstitutional, as Vinson did.

In addition to the two judges who ruled against health care reform, two others have upheld it. The matter ultimately is expected to be decided in the U.S. Supreme Court.

In the meantime, the so-called "individual mandate" has proved a potent legal argument for opponents of Obama's signature legislative achievement.

"The federal government should not be in the business of forcing you to buy health insurance and punishing you if you don't," said House Speaker John Boehner, R-Ohio. "It's not only unconstitutional, it's also unaffordable."

The White House, taking a long view of the many legal challenges to what critics call "Obamacare," is continuing to implement key provisions of the law pending a final decision by the courts. The administration plans to appeal the Florida decision.

Even so, the unfavorable rulings, combined with a lack of strong public support for the law and efforts by House Republicans to repeal it, have tarnished the luster of Obama's top accomplishment.

James W. Ely Jr., law professor emeritus at Vanderbilt University, called the individual mandate portion of the bill "simply unprecedented."

"Never before has Congress required people to buy a product or service," Ely said. "The court agreed that there is a need to improve the health care system but reminded us that even laudable goals must be achieved within constitutional limits."

Gov. Bob McDonnell of Virginia, a critic of Obama's health care reforms, said confusion over the future of the law is making it tough for states, businesses and individuals to plan for the future.

The Virginia General Assembly passed a law pre-empting enforcement of health care reform. Several other states have similar bills pending.

"This matter is far from settled," McDonnell said. "Today's decision adds to the growing uncertainty surrounding federal health care reform."

Cutter, the West Wing's lead spokeswoman for health care reform, called the Florida decision "well out of the mainstream of judicial opinion."

The administration argues that the individual mandate is similar to states requiring motorists to purchase car insurance. But the Florida judge's decision found that penalizing consumers for not buying health insurance overstepped congressional authority to regulate commerce.

"We don't let people wait until after they've been in a car accident to apply for auto insurance and get reimbursed," Cutter said, "and we don't want to do that with health care."