The Trump administration will allow states to rewrite Obamacare’s rules so that people can apply federal subsidies toward health insurance that doesn’t meet the definition laid out in the healthcare law.

The approach is controversial, with Democrats warning that people will be siphoned into “junk plans” that don’t cover medical care for pre-existing conditions such as cancer and diabetes and that it will cause further depletion of the marketplaces created under Obamacare, formally known as the Affordable Care Act.