While Democrats and Republicans in Congress get ready for November, the Obama White House is girding for the next front in the battle over health care: the courtroom.

With Republican governors like Minnesota's Tim Pawlenty urging a constitutional challenge to the bill President Obama signed Tuesday, the Justice Department is preparing to litigate, senior White House officials told reporters Wednesday. The officials, briefing on the condition that they only be named as "senior administration officials," say they're confident that they can fend off proposed legal challenges to the so-called universal mandate, the requirement that nearly everybody buy insurance (or pay a fine). Critics say it would be the first time Congress has compelled individuals to purchase a product (health insurance) in the private sector, a mandate that seems to stretch Congress' Constitutional authority. (States make you buy auto insurance, but they're not Congress). The anonymous administration officials signaled that they will rely on the Commerce Clause in the Constitution, which permits the federal government to regulate interstate commerce. If NOT buying insurance seems to some to be anything BUT engaging in interstate commerce, the White House has this answer: "It is not a decision that does not have an economic impact." So at bottom, the Obama administration will argue that uncompensated care (if you don't have insurance) costs the rest of us money and has economic implications that warrant government regulation. (Maybe those who can afford to buy insurance but refuse can carry cards in their wallets telling paramedics to just let them bleed to death). Asked whether the fines could be imposed under Congress' power to tax, the officials were ambiguous, falling back on the Commerce Clause argument. As for the so-called 10th Amendment argument that federal health care regulation usurps the power of the states (this one is also being made by Republican legislators in Minnesota), the White House says it is not forcing the states to do anything. They can set up insurance exchanges or not. (But states that don't will see the feds come in and do it for them). Thus were revealed the broad outlines of the Obama case for making you get health insurance (by 2014). Let the litigation begin.