At the center of the shutdown fight is health care. There have been many changes to health care policy under this administration, and while even more changes are coming down the pipeline, Democrats are arguing this moment in particular is key.

Tens of millions of Americans buy insurance through the Affordable Care Act exchanges, and they are one focus of Democrats' demands.

“They propose a permanent extension of Biden-era Obamacare subsidy enhancements to health insurers,” said Brian Blase, president of Paragon Health Institute.

About 24 million people use those enhancements, according to Cynthia Cox at the health policy research nonprofit KFF.

“There had been extra financial help, or enhanced premium tax credits that were lowering premiums for the last several years for people who buy their own insurance,” said Cox.

With those tax credits set to expire, people are going to start seeing higher prices when they sign up for health insurance come open enrollment in November.

“American families are going to start seeing health care costs skyrocket on the exchanges,” said Kitty Richards at economic policy thinktank Groundwork Collaborative. “And 4 million people are likely to forego coverage because they can't afford it anymore.”

Democrats are also calling to roll back changes to Medicaid — made in the summer’s big GOP reconciliation package — before they will sign on to get funding flowing again.