The tax bill that just passed the Senate eliminates the Affordable Care Act's individual mandate, and the House is likely to go along when Congress writes the final version. With the tax legislation moving so quickly and the mandate lost in the maze of so many other consequential provisions, we are not likely to have much public debate about this big change in health policy.

Expand chart Reproduced from Kaiser Family Foundation Health Tracking Poll, Nov. 8-13, 2017; Note: Question wording abbreviated, "Don't know"/"refused" responses not shown; Chart: Axios Visuals

Why it matters: If we did, even though the mandate has never been popular, our polling shows that the public does not necessarily want to eliminate it as part of tax reform legislation, once they understand how it works and what the consequences of eliminating it might be.

The back story: Republicans have targeted the ACA mandate because they want the $318 billion in savings the Congressional Budget Office says they would get to help them pay for their tax cuts. (The change would save money because fewer people would get federal subsidies on the ACA marketplaces or apply for Medicaid coverage.)

They have also targeted the mandate because they think it's so unpopular. Our polls have consistently shown that the mandate is the least popular element of the ACA and in the abstract, more Americans (55%) would eliminate the mandate than keep it (42%).

Yes, but: When people know how the mandate actually works, and are told what experts believe is likely to happen if it's eliminated, most Americans oppose repealing it in the tax plan.

When people learn that they will not be affected by the mandate if they already get insurance from their employer or from Medicare or Medicaid, 62% oppose eliminating it.

When people are told that eliminating the mandate would increase premiums for people who buy their own coverage, as the CBO says it will, they also flip, with 60% opposing eliminating the mandate.

And when they're told that 13 million fewer people will have health coverage – another CBO projection – 59% oppose eliminating the mandate.

The bottom line: Many people change their minds when they learn more about facts and consequences, which happens as the lights shine brighter on them in legislative debates. This happened to the “skinny repeal" proposal, and it would happen to single payer.

But as the tax legislation rushes through Congress and heads to the final negotiations, there is almost no chance for the public to grasp the tradeoffs that would come from eliminating the mandate and who is affected and who is not. If they did, the polling suggests, eliminating the mandate might prove far less popular than Republicans seem to think it is.