Fourteen U.S. states filed lawsuits on Tuesday challenging the health insurance reform law signed earlier in the day by President Barack Obama, claiming the law violates the constitution.

Thirteen state attorneys general, led by Florida's Bill McCollum, who is running for governor, filed a collective lawsuit, claiming it's unconstitutional to require everyone to have healthcare coverage.

McCollum was joined by counterparts from Alabama, Colorado, Idaho, Louisiana, Michigan, Nebraska, Pennsylvania, South Carolina, South Dakota, Texas, Utah and Washington. Among them, Louisiana Attorney General James Caldwell is a Democrat, while others are all Republicans, whose party fiercely opposes the reform.

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Meanwhile, Ken Cuccinelli, Republican attorney general of Virginia, filed a separate suit challenging the law in a federal court.

Local media predicted the lawsuits will not be able to stop the healthcare reform, which would offer coverage to 32 million people previously without it, but it could keep the topic alive until the mid-term election in November.

Igor Volsky, a health care researcher affiliated with the Center for American Progress, told Xinhua that once benefits of the reform start pouring in, Republican challenges to it may well evaporate.

"It will be very difficult for Republicans to run campaigns on repealing it," he said.