How is that possible? Here’s a guide to how it will work—and what we might see on Tuesday:

Many pieces of the health care law, the Affordable Care Act, aren’t tied to the annual spending bills. Much of the health law is mandatory spending—a kind of fiscal autopilot that’s not part of the annual appropriations battle that has Congress tied in knots. The mandatory components of the health law include the subsidies to help people buy private health plans as well as the expansion of Medicaid in many states. Both of those functions will be handled through the new health insurance markets or exchanges.

Because those programs are mandatory, the Department of Health and Human Services has a lot of leeway to say whether Obamacare activities can continue—and HHS officials have made clear they’re going to use it.