By Sam Baker

More than 480 state lawmakers plan to file a brief Thursday urging the Supreme Court to uphold President Obama’s healthcare law.

The group includes at least one lawmaker from every state, including the 26 states whose attorneys general are suing to overturn the healthcare law’s individual insurance mandate. The Supreme Court is scheduled to hear oral arguments in March and will likely rule on the law this summer.

The state lawmakers say requiring almost all Americans to buy insurance falls well within Congress’s power under the Constitution’s Commerce Clause. Echoing the Justice Department’s arguments in support of the mandate, the state legislators said the Constitution gives Congress broad authority to regulate interstate commerce.

“The idea that the federal government does not have the power to address a national problem such as the health care crisis has no basis in the Constitution’s text and history,” the lawmakers’ brief says, according to a summary released Thursday.

The brief is a joint effort of the Progressive States Network, the Working Group of State Legislators for Health Reform and the Constitutional Accountability Center.

Critics of the insurance mandate say it goes beyond Congress’s ability to regulate economic activity and instead requires a particular activity. The Obama administration says the mandate simply regulates how — and whether — people pay for the healthcare services everyone will eventually use.