RICHMOND, Va. — Virginia's lawsuit challenging the Obama administration's health care reform package cleared its first legal hurdle Monday when a federal judge ruled the law raises a host of complex constitutional issues.

Virginia Attorney General Ken Cuccinelli claims in the lawsuit Congress doesn't have the authority to require citizens to buy health insurance or pay a penalty.

U.S. District Judge Henry Hudson's ruling denied the Justice Department's attempt to have the lawsuit dismissed, saying further hearings were needed to weigh the merits of the case. An Oct. 18 hearing had previously been set.

"Unquestionably, this regulation radically changes the landscape of health insurance coverage in America," Hudson wrote in his 32-page decision.

The Virginia General Assembly passed legislation this year exempting state residents from the federal coverage mandate. Hudson wrote that the attorney general had a right to defend that state law.

Cuccinelli announced in March he would challenge the national law. More than a dozen other state attorneys general have joined to file a separate lawsuit in Florida against it, but Virginia's is the first to go before a judge.

Hudson said Virginia's case raises constitutional issues — mainly whether Congress has the right under the Commerce Clause to regulate and tax a person's decision not to participate in interstate commerce.

The health care law aims to ensure coverage for all, requiring most U.S. residents to carry insurance starting in 2014.

Insurers would not be able to refuse coverage for sick people under the law, which also expands Medicaid to help the poor. It also provides tax credits to help middle-class residents pay premiums. People facing financial hardship would be exempt from the coverage requirement. However, people who can afford insurance but refuse to sign up would face a tax penalty.

On Monday, Health and Human Services Secretary Kathleen Sebelius said during a teleconference Hudson's decision was a procedural step that cleared the way for a hearing.