Repeal of the ACA is the declared goal of all Republican presidential candidates. While most have some vision of replacement, that vision tends to be highly unspecific—and still likely to radically reduce the coverage Obamacare now provides.

Jeb Bush is probably the least fire-breathing opponent of the Affordable Care Act among the Republican candidates, as worried conservatives have anxiously noted. He consistently emphasizes “replacement” alongside “repeal.” But when he speaks in anything like detail, as he did in Iowa in March, this is what he says:

The effort by the state, by the government, ought to be to try to create catastrophic coverage, where ... if you have a hardship that goes way beyond your means of paying for it, that you have—the government is there or an entity is there to help you deal with that. The rest of it ought to be shifted back where individuals are empowered to make more decisions themselves.

That’s consensus conservative doctrine. Yet to a current ACA beneficiary it must sound ominous. “If you have a hardship that goes way beyond your means of paying for it …” Even small proposed changes in Medicare have up-ended American politics. Back in 1995, the government of the United States shut down for a total of 27 days over budget fights that included a disagreement over $11 per month in Medicare Part B premiums. That shutdown framed the election of 1996, in which Bill Clinton won a second term, while Republicans lost two seats in the House (offset by a gain of two in the Senate).

Many millions of Americans have much more at stake in 2016 than $11 a month. How will their interest sway the election?

A couple of maps compiled by the Center for Equitable Growth offer some clues:

Medicaid Expansion Particularly Benefits Poor Regions of the United States

Washington Center for Equitable Growth

Not all states have taken part in the Medicaid expansion. The Supreme Court ruling upholding the constitutionality of the ACA also recognized the right of states to opt-out from the Medicaid component of the law, a right that 16 states have exercised, and another five continue to discuss. Most of the states that have expanded Medicaid would be expected to go blue in 2016 anyway. But not all: Ohio, for example, without which no GOP nominee has ever won the presidency; Indiana, for another, the reddest state in the Midwest; and Arkansas, Kentucky, Nevada, North Dakota, and West Virginia.

Affordable Care Act Subsidy Benefits Are Concentrated In The South

Washington Center for Equitable Growth

Unless the Supreme Court strikes down subsidies in the federal exchange in the pending case of King v. Burwell, ACA insurance subsidies are paid everywhere in the country. As the next map shows, eligibility for subsidy is concentrated in the red states. Not all of those eligible claim the subsidy. Many of those who do receive subsidies might be expected to vote Democratic in 2016 even if healthcare were not an issue. But some Republican-leaning voters will feel the hit—and especially in a tightly balanced state like Florida, that hit could have real consequences.